Hello again, t1gerk.
Thanks for keeping me posted. I'll guide you through the steps on how to record the return payment.
You’ll need to create a $500 deposit and post the amount to your Accounts Payable. Doing so will show that your vendor still owes you that amount.
If there's anything else that I can help you find in QuickBooks, leave a comment below. I'm here to lend a helping hand.