Welcome to the Community space, @males455.
Let me share insights to help you accomplish the task of linking the payment to a matched bill in QuickBooks Online (QBO).
In QBO, once a bill matches the expense in the banking tab, it should be marked as paid. Since you encounter an issue, you first need to verify that the expense accurately matches the bill entered in QBO. Once you link the bills correctly, QBO will recognize that the payment has been applied to them and mark them as paid.
In addition, you need to check the date of the bill in the bank feed to ensure it matches the expense and verify that the bank account on the expense matches the bank where the match is located. If not, edit the details so they match and won't reappear. You can also undo categorization and match it to the correct transactions.
Moreover, I don’t want to leave you empty-handed here. I’m adding these links to learn how to record payments toward bills and other related matters in QBO:
The Community is always available 24/7. Fill me in if you need extra help with managing your expense or bill transactions in QuickBooks Online. Your efforts are much appreciated, stay safe, @males455!