Fatal error: Index[9411] 92818 is larger than the number of atoms in the trajectory file (9591)

GROMACS version: Gromacs 2024
GROMACS modification: No
Here post your question : Gromacs reported the following error:

Fatal error:
Index[9411] 92818 is larger than the number of atoms in the
trajectory file (9591). There is a mismatch in the contents
of your -f, -s and/or -n files.

For more information and tips for troubleshooting, please check the GROMACS
website at Common errors when using GROMACS - GROMACS 2024.3 documentation

Note that major changes are planned in future for trjconv, to improve usability and utility.
Select group for centering
Selected 18: ‘center’
Select group for output
Selected 19: ‘output’

Have you checked the numbers in your index file and compared to your gro file or topology?