How to Resolve Accidentally Voided Check from Prior Period

Assuming you are sure the check will not be cashed, edit the check and change the account used to a clearing expense account, in the memo block enter VOID. You may have to create that clearing expense account first if you do not have one in the chart of accounts.

Then make a deposit in that amount and use that same clearing expense account as the source account for the deposit, use the same date as the check had.

the clearing account will now be zero, the check amount is back in the bank, and when you reconcile check off the voided check against the deposit.

That worked to clear the Voided check, but how do I apply the remaining payment to the actual bill itself, since it was re-opened as Past Due once the physical check was voided?

Actually, now that I am looking at it, the Voided check was automatically changed to $0.00 when it was voided.  Now, my clearing account shows an extra amount in it because of the deposit.  How do I resolve this issue?

Second, the prior period had already been closed so I cannot apply the electronic funds to the bill.  How do I resolve that issue?

Sorry.  I have new people on my team and I have never experienced issues like this before.