Error: CountrySpecService already in use

Hi,

When users register on our site, they see “Site is Experiencing a Technical Issue” message.

When I display the error logs on the page, I see this:

An error of type E_COMPILE_ERROR was caused in line 5 of the file /home/amqfestivalcom/public_html/wp-content/plugins/paid-memberships-pro/includes/lib/Stripe/lib/Service/CountrySpecService.php. Error message: Cannot declare class Stripe\Service\CountrySpecService, because the name is already in use

I’ve tried to update the plugin, but it didn’t help. Can you please help?

The page I need help with: [log in to see the link]