AttributeError: 'NoneType' object has no attribute 'main' in isce2 processing

[Pavithra S L]

:~/raniganj_coal/run_files$ ls
run_01_unpack_topo_reference  run_03_average_baseline        run_05_overlap_geo2rdr   run_07_pairs_misreg       run_09_fullBurst_geo2rdr   run_11_extract_stack_valid_region     run_13_grid_baseline
run_02_unpack_secondary_slc   run_04_extract_burst_overlaps  run_06_overlap_resample  run_08_timeseries_misreg  run_10_fullBurst_resample  run_12_merge_reference_secondary_slc
(insar):~/raniganj_coal/run_files$ chmod +x
chmod: missing operand after ‘+x’
Try 'chmod --help' for more information.
(insar):~/raniganj_coal/run_files$ chmod +x run_01_unpack_topo_reference
(insar) suhora@STPL1068:~/raniganj_coal/run_files$ ./run_01_unpack_topo_reference
Completed Parsing the Configuration file
Functions to be executed:
['Function-1', 'Function-2']
Running: Sentinel1_TOPS
['--dirname', '/home/suhora/raniganj_coal/data/S1A_IW_SLC__1SDV_20210105T000423_20210105T000450_035995_043787_964C.zip', '--swaths', '1 2 3', '--orbitdir', '/home/suhora/raniganj_coal/orbit_files', '--outdir', '/home/suhora/raniganj_coal/reference', '--auxdir', '/home/suhora/raniganj_coal/auxFile', '--pol', 'vv']
module Sentinel1_TOPS not found
Traceback (most recent call last):
  File "/home/suhora/anaconda3/envs/insar/share/isce2/topsStack/SentinelWrapper.py", line 251, in <module>
    main(args.start,args.end)
  File "/home/suhora/anaconda3/envs/insar/share/isce2/topsStack/SentinelWrapper.py", line 242, in main
    cfgParser.runCmd()
  File "/home/suhora/anaconda3/envs/insar/share/isce2/topsStack/SentinelWrapper.py", line 54, in runCmd
    func_modules.main(self.funcParams[section])
AttributeError: 'NoneType' object has no attribute 'main'

I'm using isce2 for the preprocessing of slc data and after generating the run_files im facing this error raceback (most recent call last):
  File "/home/suhora/anaconda3/envs/insar/share/isce2/topsStack/SentinelWrapper.py", line 251, in <module>
    main(args.start,args.end)
  File "/home/suhora/anaconda3/envs/insar/share/isce2/topsStack/SentinelWrapper.py", line 242, in main
    cfgParser.runCmd()
  File "/home/suhora/anaconda3/envs/insar/share/isce2/topsStack/SentinelWrapper.py", line 54, in runCmd
    func_modules.main(self.funcParams[section])
AttributeError: 'NoneType' object has no attribute 'main'  
Packages required for isce2 is already installed and verified.
conda list | grep -i isce
isce2                        2.6.3            py38h18c7515_0          conda-forge
Kindly help me out so that i can continue with the rest.
With regards
Pavithra S l