FATAL ERROR: Error in Ambertoppar readparm(const char *filename)

[saikat0003]

I am trying to run the tutorial (https://github.com/UCL-CCS/TIES_MD/tree/main/TIES_MD/examples/NAMD/ethane_namd/zero_sum/leg1) using the same prmtop and pdb files. However, I am getting the following error: Info: USING ARITHMETIC MEAN TO COMBINE L-J SIGMA PARAMETERS Info: === Start reading AMBER parm7 format file /home/saikat/saikat/TIES/tut-1/build/sys_solv.prmtop === ERROR: Failed to read AMBER parm7 file: /home/saikat/saikat/TIES/tut-1/build/sys_solv.prmtop at read_amber_parm_stage1 FATAL ERROR: Error in Ambertoppar readparm(const char *filename)

Please guide me to solve the issue.