Hello !
After additional research, I understood that the problem is linked to the management of the sections by LATEX.
There is a suitable snippet on Tex.Stackexchange to realize what I need,
Force Latex to allow orphan line at bottom---------------------------------------------------------------------------
% SNIPPET StackExchange = allow orphan-line at page-bottom
\makeatletter%
\renewcommand\@afterheading{%
\@nobreaktrue
\everypar{%
\if@nobreak
\@nobreakfalse \clubpenalty 1
\if@afterindent \else {\setbox\z@\lastbox}
\fi
\else
\clubpenalty 1
\everypar{}%
\fi}%
}
\makeatother%
-----------------------------------------------------------------------------
Sincerely