Oracle Error Message
RMAN-05560: Using previous duplicated file string for datafile number with checkpoint SCN of string
Reason for the Error
A datafile copy from a previous duplicate attempt matching the duplicate name requested was found for the specified datafile and will be used instead of restoring the datafile from a backup.
Solution
No action needed unless this behavior is not desire. In that case, either use a different name for the datafile or use NORESUME to avoid using previous datafile copies for all the datafiles.