You can't open a bill that's already paid, change the amount or vendor, and save it as if nothing happened, the linked payment won't update to match. The real fix is to unapply or delete the bill payment first, which flips the bill back to open, correct the bill itself, then redo the payment against the fixed version.
1. Find the bill and the payment attached to it. Open the bill from Expenses > Vendors, or from the vendor's own profile. You'll see it marked Paid, with a link to the Bill Payment (check) or credit card transaction that paid it.
2. Open that payment and unapply or delete it. Click through to the Bill Payment, then choose More at the bottom and either Delete if the payment shouldn't exist as recorded, or void it if you want to keep the check number on record but strip out the amount. Either way, the bill it was attached to goes back to Open.
3. Edit the bill now that it's unpaid. With the payment out of the way, the bill behaves like any other open bill, change the amount, the date, the vendor, or the line items, whatever was actually wrong.
4. Redo the payment against the corrected bill. Go to Pay Bills, select the corrected bill, and record the payment again. If the original payment already cleared your bank and you don't want that side of things to move, match the date and method so the bank side stays the same, you're just fixing what it was actually paying for.
5. Check whether that period's already reconciled. If the original payment was part of a bank reconciliation that's already closed, deleting and redoing it can throw that reconciliation out of balance. Confirm with whoever closed the books before you touch a bill payment from a closed month.
The mistake usually isn't caught at the moment the bill's entered, it's caught weeks later, after the bill's already gone through Pay Bills in a batch with a dozen other vendors. By then unwinding just the one wrong bill without disturbing the rest of that batch takes care, and it's easy to delete the wrong payment or forget to redo it at all.
Most of the actual time lost here isn't the unwind itself, it's that nobody catches the error until after the money's already moved. The amount was wrong, or the bill got coded to the wrong vendor, and it only surfaces once someone's reconciling the account or the vendor calls asking why they were paid the wrong amount.
The bill amount gets compared automatically against a purchase order or packing slip from another system before it's queued in Pay Bills, so a wrong amount gets caught before the payment goes out, not after.
The moment someone deletes or voids a bill payment to fix a mistake, whoever manages AP gets notified automatically, instead of a correction happening quietly with no record anyone else sees it.
Tell us where the mismatch usually comes from, a typo, a wrong vendor, a quantity that changed after the PO went out, and we'll tell you if it's catchable before the payment runs.
Tell us how bill errors actually get caught in your business, before payment or after, and we'll tell you whether that catch can happen earlier automatically. Bill payments are just one place manual work hides; n-frames looks at whatever's eating time by hand, any tool, any process, not only this one.
Let's talk →Open the Bill Payment (or the credit card charge that paid it) from the vendor's transaction list, then delete or void it. Either action sends the bill it was attached to back to Open, ready to be corrected or paid again.
Delete the bill payment first, then delete the bill itself, in that order. Deleting the bill while a payment's still linked to it leaves an orphaned payment sitting in your books with nothing to reconcile against, which is usually a bigger mess than the one you started with.
Same idea, different transaction type: find the credit card charge that recorded the payment and delete or void it there instead of in the check register. The bill flips back to unpaid either way, regardless of which payment method covered it.
It can, if the original payment already cleared and that statement period is already reconciled. Check the reconciliation status before you touch it; if the month's closed, matching the same date and amount on the redone payment usually keeps the reconciliation from shifting.