When this happens one may think to add some prefix to avoid running out of limits. This techdoc adds another possibility--The format name is not created if there is already an existing format name.
Release : 8.6/8.7
Component : CA 2E
The format name is not created if there is already an existing format name.
Check DDS file to see if another file had already used the format names. If yes, a unique format name for the missing format names would need to be added manually.