Error During OnZoom Registration

Hello,

OnZoom has been great for months. 

Recently some participants told me they could not sign up for my event. When they go to pay for a ticket (drop-in or for the entire series) they get an error message that simply says, "An error was encountered while processing your request."

I tried purchasing a ticket using another Zoom account, and I got the same error right at the point of submitting the payment.  I've also tried creating special tickets for the participants using discounted and free email-invite tickets. Those don't work either. 

One participant is registered for the entire series. He registered last month when I originally posted the event at OnZoom. He can log in just fine, but I'm losing drop-in participants. 

Anyone have similar issues? Any ideas about how to remedy the issues is greatly appreciated.

Thank you!