How do i fix this error when settling an invoice - "You can only use one foreign currency per transaction".?

Hi,  @Chipo-Chubili. Can you confirm your customer’s currency and the currency of the bank or payment account?

When multicurrency is enabled in QuickBooks Online, each transaction can only use one foreign currency. If you try to pay an invoice from your home currency (USD) to a foreign currency (like EUR), and your Deposit To bank is in a different currency (like CAD), QuickBooks will show an error: "You can only use one foreign currency per transaction." This means you can’t mix different foreign currencies in a single transaction.

 
To avoid this error, make sure the bank account you’re depositing to is either in your home currency or the same currency as your customer.

Let us know if you have further question or concern.