It's a pleasure to have you here in the Community, Meriam!
May I know what specific error you encountered when you tried to match a payment to the invoice?
When you experience issues while matching a payment to the invoice, it could be due to inaccuracies in the details. Make sure to double-check the customer, invoice, payment date, and amount to ensure they are entered correctly.
In QuickBooks Online (QBO), transactions may not appear when you attempt to Find Match due to various reasons. If the transaction has already been reconciled, entered in QBO, and matched to another downloaded transaction, or downloaded twice, it won't be available for matching. Also, processing fees can cause differences in the amounts.
For a more in-depth guide on the process, you can refer to this article: Match online bank transactions in QuickBooks Online.
In case you want to personalise your sales forms, check out this article for further guidance: Customise invoices, estimates, and sales receipts in QuickBooks Online.
If you have any other questions or need further assistance with recording payments, feel free to ask here. I'm always here to help. Take care and have a good one!