Paypal recurring payments failed after merging the contact. How to fix?
Could you create a new contact with just a first and last name (no address, phone, or anything else that might go in a separate table somewhere) and then change that new contact's ID in the database to 1212? Then you could merge again, making sure to keep the new contact and transfer all of the other information over during the merge. (Try on a copy of the database of course)