How do I rotate images in the payments module?

The image of the invoices in the payments details view is reflected directly from the Invoices Module. In order to change the orientation of the invoice, you'll need to go into the details view of the invoice and rotate the page there.

See our support article here on how to view the invoice details from the Payments module.
 
See our support article here on how to rotate an invoice page in the Invoices module.