if you get this error in backup logs , there could be various reasons as specified below ...
1)
MOS : 342696.1
The controlfile which is being used, is older than the controlfile used for last resync.
The
error stack is generated when the controfile sequence is less than the
sequence used during the last resync. This would indicate that an old
controlfile is being used.
Solution : Recreate the target database controlfile. or Create a new catalog for this target.
2)
There could be another session that has been trying to resync the catalog or simply accessing the snapshot controlfile.
Hope this helps
SRI