They even have a whole Zoom case study! https://www.zuora.com/our-customers/case-studies/zoom/

It's subscription/billing management, and it doesn't really do payment processing itself, but rather you might configure Zuora with something like Stripe/PayPal/etc.

Gitlab had an outage today related to Zuora going down. My guess is the backends directly call to these APIs and they don't have any form of caching or storing the info from these APIs elsewhere.

Zuora has been having issues today (and this weekend past).

https://trust.zuora.com/

Looks like another Cisco Webex spin out - like Zoom