I have a following error message when running proc py. The same script was running successfully for the other condition of this participant, but it continuously shows this error message for this condition. Could you please let me know, what is the issue and how to resolve it?

Warping used up maximum iterations even after doubling number of iterations to 274.
Convergence might not have been reached.
If you find the alignment poor, try
rerunning the script with a transform
type of fewer parameters (-xform) or by using
an even higher number of iterations (-maxite).
You can also choose to continue with the
current result (dset: __ats_tmp__reg_warpdriveout+orig
by using the option: -OK_maxite

Script will stop …

cat_matvec mprage.Subject#.Rest_al_keep_MNI152+tlrc::WARP_DATA -I
** ERROR: THD_read_dvecmat: can’t open dataset mprage.Subject#.Rest_al_keep_MNI152+tlrc
** FATAL ERROR: Can’t read matrix from ‘mprage.Subject#_al_keep_MNI152+tlrc::WARP_DATA’