Payment Error of Zoom Webinar

I would like to buy a Zoom Webinar for 5,000 attendees to watch our live. However, I cannot make the payment successfully during the online payment by using credit card. The following statement shown below:

''Error! The system could not process your request at this time, please try again later or using another payment method. If the problem persists please contact your bank or try a different payment method. If the issue persists, please submit a request to Zoom for assistance.''

Could anyone help me to figure out the problem? THANKS!!!