Adding a payment method to an invoice in QuickBooks Online (QBO) International is unavailable; it's only possible in the US versions. Consider exploring third-party applications for assistance with invoice payment. You can find one by visiting this website: https://quickbooks.intuit.com/app/apps/home/en-global/.
You can also use the Apps feature in your account. Here's how:
Go to the Apps menu.
Click Find Apps.
From there, you can see an application that suits your business needs.
Additionally, I've added this link about recording customer payments in QuickBooks: Record invoice payments.
Furthermore, by connecting your bank account and receiving the deposit from your customer, you can visit this page to link the bank deposit to an invoice.
I'll be here if you have other questions about adding a payment method in QuickBooks. Take care and stay safe.
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