Journal Entries

My bank was bought out by another bank, so I have new bank acounts connected to Stessa. Stessa is still showing balances for my old accounts which have been transferred to the new bank.
How do I create a journal entry that zeros out my original bank accounts that were transferred to the new accounts. Right now, the old accounts are showing up with balances that no longer exist. I want to keep the history, so I don’t want to delete those accounts, but I need the 2 original accounts to show a zero balance. How is this accomplished?