Errors in transmembrane protein simulation

GROMACS version:2020
GROMACS modification: Yes
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Hello all,
I am simulating a transmembrane protein with a docked ligand. The input files for protein, membrane, and water molecules were taken from charmm membrane builder, I also used ATB for the ligand itp file.
I run energy minimization and it ended normally, then for the NVT equilibration I got errors like:

ERROR 9526 [file PROA.itp, line 190603]:
No default Position Rest. types

ERROR 9527 [file CHL1.itp, line 845]:
Incorrect number of parameters - found 2, expected 3 or 6 for Position
Rest. (after the function type).

I appreciate any help to fix this problem,
Thank you in advance,
Havva Mehralitabar

Here’s your problem. You’re trying to mix two different force fields. Don’t. Build everything in CHARMM or build everything in GROMOS, not a combination of the two. The CHARMM-GUI server can call CGenFF to parametrize ligands.

Thank you so much for the help