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On the left navigation, click Sales > Invoices.
Find and select an invoice belonging to the account you want to add a payment method to.
Click the Receive Payment icon.
Amount: Input the amount to be charged.
Method: Select Select Charge New Credit Card or Charge New ACH as required.
Enter the payment information and click Save Payment
The payment method will be charged and after the page refreshes should appear as a payment option under both the Receive Payment and Schedule Payment links
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