Getting error while generating processed.gro

GROMACS version: 2021.3
GROMACS modification: Yes/No
Here post your question : while generating processed.gro it is showing error like Residue 27 named ASP of a molecule in the input file was mapped to an entry in the topology database, bu the atom CG used in that entry is not found in the input. perhaps your atom and/or residue naming needs to be fixed. how to rectify it.

Thanking you,

You have to model in any missing atoms before running pdb2gmx.

Thank you sir