When I click "receive payment" from an existing invoice and then choose "save and send" the document that is sent to the customer is not the default receipt I designed.

The invoice payment receipt and sales receipt are different, BETTERhome. I can discuss this further to provide more insight.

The option to modify the invoice payment receipt form is currently unavailable in QuickBooks Online. An invoice payment receipt and a sales receipt are two different transactions. This distinction explains why your customized and default forms were not utilized, as they are specifically designed for sales receipt entries.

On the other hand, you can run several reports to review the products or services you buy and sell and the status of your inventory with the guide of this material: Use reports to see your sales and inventory status in QuickBooks Online.

We encourage you to connect with us in this forum whenever you have questions about personalising your sales forms in QuickBooks Online. Our team is here to assist you and ensure you get your needed support.