Problem
An email was sent to a customer but once the customer clicked the link to pay the invoice, they could only select ACH or Credit Card as a payment method, not both. ACH and Credit Card are both enabled under Online Payment settings.
Solution
The most common reason for a payment method to be missing from the emailed payment link is because the business unit is not set up for the payment processor.
Add business unit to the payment type
Go to the navigation bar and click Settings
.In the side panel, go to Integrations > Payment Processing.
Select the tab for the payment.

Look for the account you use and click Edit.
On the Online Payments Account screen that opens, select the business unit you want to include.

When finished, click Save.