Gromacs Gro file format problem

GROMACS version: 2021
GROMACS modification: Yes/No
I have a large gromacs spece.gro file. I am using trjconv to get the spce water position velocities from .trr file. I have noticed this with regular .gro file as well. Why its column 1&2 getting attached after 10000 rows. Please see an example below,

3573SOL OW 9997 3.948 4.918 5.552 -0.5688 0.3562 -0.5804
3573SOL HW1 9998 3.929 5.014 5.534 -0.7157 0.5941 0.7435
3573SOL HW2 9999 3.866 4.874 5.589 -0.3718 -0.1701 -0.7598
3574SOL OW10000 3.924 1.240 1.568 -0.1950 0.9684 0.6467
3574SOL HW110001 3.968 1.308 1.627 0.0634 1.0487 0.3640
3574SOL HW210002 3.924 1.151 1.614 -0.1122 1.0584 0.8220
3575SOL OW10003 4.374 4.506 0.546 0.5154 -0.1469 0.0109
3575SOL HW110004 4.303 4.535 0.611 0.4903 -1.0085 0.3816

Hi!
I’m not sure what the issue is here. Can you specify what kind of error you get?