402 Payment Required

Reserved for future use. Some APIs send it for an unpaid account, with no standard meaning.

Class
4xx Client Error. The request has a fault, or cannot be met as sent.
Registered
Yes, in the IANA HTTP status code registry.
Cacheable by default
No. A cache stores it only when Cache-Control or Expires says to.
References
RFC 9110 ยง15.5.3 · MDN

Every 4xx code

All HTTP status codes, in one table