Hi, Todd.
When you use the Send Payment Link feature in QuickBooks Online, it generates a separate Sales Receipt because this option is designed for receiving payments that are not directly tied to an existing invoice. This is why the payment you receive through the payment link does not automatically reduce the balance of the actual invoice.
To ensure the payment applies directly to the customer's invoice and reduces the balance, here’s what you can do:
- Navigate to the Create + in the left-hand navigation bar.
- Select Receive Payment.
- Choose the customer who made the payment.
- Under the Outstanding Transactions section, select the appropriate invoice.
- Under the Credits section, look for and apply the Sales Receipt (payment generated from the payment link) to the invoice.
- Click Save and close.
For more information about the Send Payment Link feature, I recommend reviewing this article: Send Payment Links.
If you need further questions or help, feel free to comment below.