Program: gmx pdb2gmx, version 2021.4-Ubuntu-2021.4-2 Source file: src/gromacs/gmxpreprocess/resa

The problem is that the force field does not recognize that phospolipid. The explanation is in Common errors when using GROMACS - GROMACS 2024.1 documentation.

As I said, the related topics, below your post, is also useful, such as: Fatal error: Residue 'EDO' not found in residue topology database - #4 by jalemkul and Fatal error: Residue "NAG' not found in residue topology database.