Estou utilizando o template abnteX2, e especificamente nas minhas tabelas "longtable" estão aparecendo esses erros, e não consigo resolver de forma alguma.
Segue abaixo o código de uma das tabelas.
\begin{document}
\usepackage{lmodern} % Usa a fonte Latin Modern
\usepackage[T1]{fontenc} % Selecao de codigos de fonte.
\usepackage[utf8]{inputenc} % Codificacao do documento (conversão automática dos acentos)
\usepackage{indentfirst} % Indenta o primeiro parágrafo de cada seção.
\usepackage{color} % Controle das cores
\usepackage{graphicx} % Inclusão de gráficos
\usepackage{microtype} % para melhorias de justificação
\usepackage{array}
\usepackage{multirow}
\usepackage{rotating}
\usepackage{longtable, booktabs}
\usepackage{pdflscape}
\usepackage{caption}
\usepackage{subcaption}
\usepackage[table,xcdraw]{xcolor}
\begin{landscape}
\footnotesize
\begin{longtable}{p{2.5cm}p{0.8cm}p{1.8cm}p{0.5cm}p{0.5cm}p{0.5cm}p{0.7cm}p{0.5cm}p{0.5cm}p{0.5cm}p{0.5cm}p{0.5cm}p{0.7cm}p{0.7cm}p{0.5cm}p{0.5cm}p{0.7cm}p{0.7cm}p{1.7cm}p{1cm}}
\caption{Database of bending tests on steel-UHPC composite beams.}
\label{table2-6}
\hline
\multirow{3}{*}{Author} & \multirow{3}{*}{System} & \multirow{3}{*}{Test setup} & \multirow{2}{*}{Span} & \multicolumn{4}{l}{Concrete slab} & \multicolumn{6}{l}{Steel beam} & \multicolumn{6}{l}{Shear connectors} \\
& & & & $b_c$ & $h_c$ & $f_c$ & $V_f$ & $b_f$ & $t_w$ & $t_f$ & $h$ & $f_y$ & $f_u$ & $d_{cs}$ & $h_{cs}$ & $f_y$ & $f_u$ & \multirow{2}{*}{Arr.} & \multirow{2}{*}{Fix.} \\
& & & (m) & (mm) & (mm) & (MPa) & (\%) & (mm) & (mm) & (mm) & (mm) & (MPa) & (MPa) & (mm) & (mm) & (MPa) & (MPa) & & \hline \endfirsthead
\caption{(continued)}
\hline
\multirow{3}{*}{Author} & \multirow{3}{*}{System} & \multirow{3}{*}{Test setup} & \multirow{2}{*}{Span} & \multicolumn{4}{l}{Concrete slab} & \multicolumn{6}{l}{Steel beam} & \multicolumn{6}{l}{Shear connectors} \\
& & & & $b_c$ & $h_c$ & $f_c$ & $V_f$ & $b_f$ & $t_w$ & $t_f$ & $h$ & $f_y$ & $f_u$ & $d_{cs}$ & $h_{cs}$ & $f_y$ & $f_u$ & \multirow{2}{*}{Arr.} & \multirow{2}{*}{Fix.} \\
& & & (m) & (mm) & (mm) & (MPa) & (\%) & (mm) & (mm) & (mm) & (mm) & (MPa) & (MPa) & (mm) & (mm) & (MPa) & (MPa) & & \hline \endhead
\multirow{2}{*}{Yoo and Choo [26]} & \multirow{2}{*}{M} & \multirow{2}{*}{4PBT} & \multirow{2}{*}{2} & \multirow{2}{*}{248} & 50 & 59 & \multirow{2}{*}{2} & \multirow{2}{*}{225} & \multirow{2}{*}{8} & \multirow{2}{*}{13} & \multirow{2}{*}{150} & \multirow{2}{*}{396} & \multirow{2}{*}{554} & \multirow{2}{*}{13} & \multirow{2}{*}{50} & \multirow{2}{*}{370} & \multirow{2}{*}{470} & \multirow{2}{*}{1CR\textsuperscript{a}} & \multirow{2}{*}{W} \\
& & & & & 100 & 183 & & & & & & & & & & & & & \\
\multirow{3}{*}{Choi et al. [103]} & \multirow{3}{*}{M} & \multirow{3}{*}{4PBT} & \multirow{3}{*}{2} & \multirow{3}{*}{248} & 50 & 120 & \multirow{3}{*}{1.5} & 197 & 8 & 11.8 & 180.8 & \multirow{3}{*}{397} & \multirow{3}{*}{550} & 13 & \multirow{3}{*}{50} & \multirow{3}{*}{371} & \multirow{3}{*}{472} & \multirow{3}{*}{1CR\textsuperscript{a}} & \multirow{3}{*}{W} \\
& & & & & 100 & 150 & & 200 & 9 & 13 & 150 & & & 18.5 & & & & & \\
& & & & & & 180 & & 225 & & & 150.8 & & & & & & & & \\
\multirow{2}{*}{Wang et al. [29]} & \multirow{2}{*}{P} & \multirow{2}{*}{4PBT} & \multirow{2}{*}{8.7} & \multirow{2}{*}{1000} & \multirow{2}{*}{200} & 163 & \multirow{2}{*}{2.5} & 320\textsuperscript{b} & \multirow{2}{*}{~-} & 14\textsuperscript{b} & \multirow{2}{*}{660} & \multirow{2}{*}{354.6} & \multirow{2}{*}{568.3} & \multirow{2}{*}{22} & \multirow{2}{*}{100} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{2CR} & \multirow{2}{*}{W+B} \\
& & & & & & 164.7 & & 200\textsuperscript{c} & & 20\textsuperscript{c} & & & & & & & & & \\
\multirow{2}{*}{Wang et al. [104]} & \multirow{2}{*}{M} & \multirow{2}{*}{3PBT/4PBT} & 1.5 & \multirow{2}{*}{600} & 50 & \multirow{2}{*}{119.3} & \multirow{2}{*}{2} & 280\textsuperscript{b} & \multirow{2}{*}{12} & 8\textsuperscript{b} & \multirow{2}{*}{278} & 346.5\textsuperscript{d} & 488.5\textsuperscript{d} & \multirow{2}{*}{13} & \multirow{2}{*}{35} & \multirow{2}{*}{-} & \multirow{2}{*}{528.3} & \multirow{2}{*}{2CR} & \multirow{2}{*}{W + IT} \\
& & & 4.5 & & 60 & & & 600\textsuperscript{c} & & 20\textsuperscript{c} & & 353.2\textsuperscript{e} & 500.5\textsuperscript{e} & & & & & & \\
\multirow{2}{*}{Hu et al. [23]} & \multirow{2}{*}{P} & \multirow{2}{*}{4PBT} & \multirow{2}{*}{4.2} & \multirow{2}{*}{900} & \multirow{2}{*}{130} & 49.5 & \multirow{2}{*}{2} & \multirow{2}{*}{255} & \multirow{2}{*}{14} & \multirow{2}{*}{14} & \multirow{2}{*}{250} & \multirow{2}{*}{387.1} & \multirow{2}{*}{542.3} & \multirow{2}{*}{30} & \multirow{2}{*}{120} & \multirow{2}{*}{390.4} & \multirow{2}{*}{435.6} & \multirow{2}{*}{4GC} & \multirow{2}{*}{W} \\
& & & & & & 124.7 & & & & & & & & & & & & & \\
\multirow{3}{*}{Qi et al. [24]} & \multirow{3}{*}{P} & \multirow{3}{*}{4PBT} & \multirow{3}{*}{4.2} & \multirow{3}{*}{900} & \multirow{3}{*}{130} & 49 & \multirow{3}{*}{2} & \multirow{3}{*}{255} & \multirow{3}{*}{14} & \multirow{3}{*}{14} & \multirow{3}{*}{250} & \multirow{3}{*}{360} & \multirow{3}{*}{505} & \multirow{3}{*}{30} & \multirow{3}{*}{120} & \multirow{3}{*}{390.4} & \multirow{3}{*}{435.6} & \multirow{3}{*}{4GC} & \multirow{3}{*}{W} \\
& & & & & & 124 & & & & & & & & & & & & & \\
& & & & & & 125 & & & & & & & & & & & & & \\
Zhu et al. [15] & M & 4PBT & 3.51 & 810 & 90 & 171 & 3 & 200 & 8 & 12 & 200 & 420 & - & 16 & 65 & 320 & 400 & 9GC / 2CR & W \\
\multirow{2}{*}{Zhu et al. [22]} & \multirow{2}{*}{M} & \multirow{2}{*}{3PBT} & \multirow{2}{*}{1.84} & \multirow{2}{*}{500} & \multirow{2}{*}{55} & 52.6 & \multirow{2}{*}{3} & \multirow{2}{*}{-} & \multirow{2}{*}{8} & 10\textsuperscript{b} & \multirow{2}{*}{222} & \multirow{2}{*}{418.21} & \multirow{2}{*}{540.35} & \multirow{2}{*}{13} & \multirow{2}{*}{42} & \multirow{2}{*}{400} & \multirow{2}{*}{-} & \multirow{2}{*}{2CR} & \multirow{2}{*}{W} \\
& & & & & & 170 & & & & 12\textsuperscript{c} & & & & & & & & & \\
\multirow{3}{*}{Zhu et al. [105]} & \multirow{3}{*}{M} & \multirow{3}{*}{4PBT} & 1.56 & 550 & 90 & \multirow{3}{*}{171} & \multirow{3}{*}{3} & \multirow{3}{*}{200} & \multirow{3}{*}{8} & \multirow{3}{*}{12} & \multirow{3}{*}{200} & \multirow{3}{*}{387} & \multirow{3}{*}{556} & \multirow{3}{*}{16} & \multirow{3}{*}{65} & \multirow{3}{*}{540} & \multirow{3}{*}{571} & \multirow{3}{*}{2CR / 3CR} & \multirow{3}{*}{W} \\
& & & 1.82 & 810 & 120 & & & & & & & & & & & & & & \\
& & & 2.34 & & & & & & & & & & & & & & & & \\
\multirow{3}{*}{Liu et al. [106]} & \multirow{3}{*}{M} & \multirow{3}{*}{4PBT} & \multirow{3}{*}{5} & \multirow{3}{*}{600} & 90 & 60.5 & \multirow{3}{*}{2} & \multirow{3}{*}{175} & \multirow{3}{*}{7} & \multirow{3}{*}{11} & \multirow{3}{*}{350} & 224.2\textsuperscript{d} & 342.7\textsuperscript{d} & \multirow{3}{*}{16} & \multirow{3}{*}{70; 80} & \multirow{3}{*}{-} & \multirow{3}{*}{480} & \multirow{3}{*}{2CR} & \multirow{3}{*}{W} \\
& & & & & 100 & 133.3 & & & & & & 282.4\textsuperscript{e} & 396.9\textsuperscript{e} & & & & & & \\
& & & & & 125 & & & & & & & & & & & & & & \\
\multirow{2}{*}{Zhang et al. [18]} & \multirow{2}{*}{M} & \multirow{2}{*}{3PBT} & \multirow{2}{*}{1.84} & \multirow{2}{*}{500} & \multirow{2}{*}{55} & \multirow{2}{*}{52.6 / 170} & \multirow{2}{*}{3} & \multirow{2}{*}{130} & \multirow{2}{*}{8} & 10\textsuperscript{b} & \multirow{2}{*}{225} & \multirow{2}{*}{418.21} & \multirow{2}{*}{540.35} & 13 & 42 & 400 & - & \multirow{2}{*}{2CR} & W \\
& & & & & & & & & & 12\textsuperscript{c} & & & & 14 & 80 & 640 & - & & B \\
\multirow{2}{*}{Zhu et al. [17]} & \multirow{2}{*}{M} & \multirow{2}{*}{4PBT} & \multirow{2}{*}{3.51} & \multirow{2}{*}{810} & \multirow{2}{*}{90} & \multirow{2}{*}{171} & \multirow{2}{*}{3} & \multirow{2}{*}{200} & \multirow{2}{*}{8} & \multirow{2}{*}{12} & \multirow{2}{*}{200} & 378\textsuperscript{d} & 549\textsuperscript{d} & \multirow{2}{*}{16} & \multirow{2}{*}{65} & \multirow{2}{*}{320} & \multirow{2}{*}{400} & \multirow{2}{*}{2CR} & \multirow{2}{*}{W} \\
& & & & & & & & & & & & 396\textsuperscript{e} & 564\textsuperscript{e} & & & & & & \\
\multirow{2}{*}{Liu et al. [30]} & \multirow{2}{*}{M} & \multirow{2}{*}{3PBT} & \multirow{2}{*}{3.2} & \multirow{2}{*}{600} & \multirow{2}{*}{60} & \multirow{2}{*}{152.3} & \multirow{2}{*}{2.5} & 190\textsuperscript{b} & \multirow{2}{*}{8} & 8\textsuperscript{b} & \multirow{2}{*}{268} & 360.1\textsuperscript{d} & \multirow{2}{*}{-} & \multirow{2}{*}{10} & \multirow{2}{*}{40} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{2CR} & \multirow{2}{*}{W} \\
& & & & & & & & 120\textsuperscript{c} & & 10\textsuperscript{c} & & 353.7\textsuperscript{e} & & & & & & & \\
Lu et al. [41] & M & 3PBT & 4 & 700 & 54 & 112 & 2 & 250 & 10 & 16 & 260 & 460 & 550 & 22 & 70 & 263 & 410 & 2CR / 3GC & W \\
Shi et al. [107] & M & 3PBT & 3 & 1250 & 100 & 103 & 0 & 250 & 9 & 14 & 250 & 367 & 511 & 19 & 80 & 506 & 600 & 2CR & W \\
Wan et al. [40] & M & 3PBT & 4.2 & 1200 & 160 & 125 & 2 & 400 & 24 & 36 & 400 & 523 & 704 & 20 & 120 & - & - & 3CR & W \\
\multirow{2}{*}{Zhu et al. [108]} & \multirow{2}{*}{M} & \multirow{2}{*}{3PBT} & \multirow{2}{*}{2.12} & \multirow{2}{*}{615} & \multirow{2}{*}{90} & \multirow{2}{*}{137} & \multirow{2}{*}{3} & \multirow{2}{*}{175} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{175} & 422.6\textsuperscript{d} & 587.1\textsuperscript{d} & 13 & 25 & - & - & \multirow{2}{*}{2CR} & \multirow{2}{*}{W} \\
& & & & & & & & & & & & 451.6\textsuperscript{e} & 583.6\textsuperscript{e} & 16 & 65 & - & - & & \\
\multirow{2}{*}{Tong et al. [102]} & \multirow{2}{*}{M/P} & \multirow{2}{*}{4PBT} & 3 & \multirow{2}{*}{580} & \multirow{2}{*}{100} & \multirow{2}{*}{140.1} & \multirow{2}{*}{2.2} & 175\textsuperscript{b} & \multirow{2}{*}{10} & \multirow{2}{*}{20} & \multirow{2}{*}{350} & 794\textsuperscript{d} & 889\textsuperscript{d} & 13 & 80 & 373 & 455 & \multirow{2}{*}{9GC / 2CR} & \multirow{2}{*}{W} \\
& & & 3.2 & & & & & 230\textsuperscript{c} & & & & 777\textsuperscript{e} & 870\textsuperscript{e} & 19 & 80 & 375 & 458 & & \\
\multirow{2}{*}{He et al. [37]} & \multirow{2}{*}{M} & \multirow{2}{*}{4PBT} & \multirow{2}{*}{2.3} & \multirow{2}{*}{450} & 80 & \multirow{2}{*}{124} & \multirow{2}{*}{2} & \multirow{2}{*}{80} & \multirow{2}{*}{8} & \multirow{2}{*}{8} & \multirow{2}{*}{140} & \multirow{2}{*}{523} & \multirow{2}{*}{704} & \multirow{2}{*}{8} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{-} & \multirow{2}{*}{PSC} & \multirow{2}{*}{W} \\
& & & & & 100 & & & & & & & & & & & & & & \\
\multirow{3}{*}{He et al. [109]} & \multirow{3}{*}{M} & \multirow{3}{*}{4PBT} & \multirow{3}{*}{2.3} & 450 & 80 & \multirow{3}{*}{124} & \multirow{3}{*}{2} & \multirow{3}{*}{80} & \multirow{3}{*}{8} & \multirow{3}{*}{8} & \multirow{3}{*}{140} & \multirow{3}{*}{523} & \multirow{3}{*}{704} & \multirow{3}{*}{8} & \multirow{3}{*}{-} & \multirow{3}{*}{-} & \multirow{3}{*}{-} & \multirow{3}{*}{PSC} & \multirow{3}{*}{W} \\
& & & & 550 & 100 & & & & & & & & & & & & & & \\
& & & & & 110 & & & & & & & & & & & & & & \\
\multirow{2}{*}{Fang et al. [67]} & \multirow{2}{*}{P} & \multirow{2}{*}{4PBT} & \multirow{2}{*}{2.4} & \multirow{2}{*}{600} & \multirow{2}{*}{75} & 45.19 & \multirow{2}{*}{2} & \multirow{2}{*}{255} & \multirow{2}{*}{14} & \multirow{2}{*}{14} & \multirow{2}{*}{250} & \multirow{2}{*}{256.66} & \multirow{2}{*}{440.62} & 22 & 60 & 371.23 & 491.21 & \multirow{2}{*}{4GC} & W \\
& & & & & & 145.45 & & & & & & & & 22 & - & 670.54 & 891.68 & & B \\ \hline
\end{longtable}
\raggedright
\footnotesize
[Note] $M$ = monolithic slab, $P$ = precast slab, $b_c$ = slab width, $h_c$ = slab depth, $f_c$ = concrete compressive strength, $V_f$ = fiber volume fraction, $b_f$ = flange width, $t_w$ = web thickness, $t_f$ = flange thickness, $h$ = steel beam depth, $f_y$ = yield stress, $f_u$ = ultimate strength, $d_{cs}$ = connector diameter, $h_{cs}$ = connector height, $3PBT$ = three-point bending test, $4PBT$ = four point bending test, $\#CR$ = $\#$ connector row, $\#GC$ = $\#$ grouped connectors, $PSC$ = perfobond strip connectors, $Arr.$ = Arrangement, $Fix.$ = Fixation, $W$ = welded, $IT$ = interface treatment, and $B$ = bolted.
\textsuperscript{a} Welded on each side of the web, \textsuperscript{b} upper flange, \textsuperscript{c} lower flange, \textsuperscript{d} flange, and \textsuperscript{e} web
\end{landscape}
\end{document}