Hi KathyL69,
That's a real pain, especially when it's affecting multiple clients trying to pay. One thing to double check first is the invoice link that was attached. Sometimes the "Pay" button can go missing or act up if the link isn't quite right or hasn't been pulled through properly. You can resend the invoice using the online invoice link to make sure they're getting the correct one. Here's a guide on how to do that: Sending an online invoice link to a customer.
If it's still doing the endless spin or the button's missing after that, best bet is to jump onto our live chat support through our virtual assistant, MOCA, or submit a case via My Account so the team can take a closer look from our end.
Regards,
Sai