Bill Pay voided an uncashed check

Thanks for posting in the Community, @kellysawin1.

Based on that information, you can create a vendor credit first. This will ensure the credit hits the expense account you use for this vendor.

Here's how:

1. In QuickBooks Online (QBO), go to the + New option at the upper left to create a Vendor credit. 
2. In the Vendor drop-down, select your vendor.
3. Depending on how you record purchases with this vendor, enter the Category details or Item details.
4. Hit Save and close.

After that, deposit it to the Accounts Payable so you can tie the refund to the vendor credit. Here's how:

1. Go back to the + New option and select Bank Deposit. 
2. In the Account drop-down menu, select the account where you got the refund.
3. In the Add funds to this deposit section, choose the vendor in the Received from section.
4. Pick Accounts Payable in the Account, then the payment method and amount.
5. Hit Save and close.

Once done, link them together using the Pay Bills option. Please refer to this article and proceed to Step 3 for further guidance: Enter a refund from a vendor.

You can also run the Expenses by Vendor Summary report to view your total expenses for each vendor. Just go to the Reports menu at the left pane.

Don't hesitate to leave a comment below if you have any other concerns. I'll be here to help. Have an amazing rest of the day!