I appreciate you for joining the thread, @carol20.
Let me provide some information about modifying your account for bills in QuickBooks Online.
Accounts Payable is a default account to identify all money out movement. As a balance of all bills, it will affect the Accounts Payable account. Thus, it's not an eligible account to use since it's a default account. This is why you're only able to edit the Expense category.
Moreover, you can seek professional advice from your accountant to ensure the accuracy of your accounts if you use Journal Entry to move balances. If you're not affiliated with one, you can utilize our accountant to look for one in your area.
You can also read through this guide for more details about tracking bills and recording bill payments: Enter and manage bills and bill payments in QuickBooks Online.
This resource can help you if you want to delete or void a bill or bill payment: Void or delete a bill or bill payment check.
You can always tag me in your response if you have any other questions about bills or recording your payments in QBO. I'll be available to assist you at any time. Keep safe.
