PaygateDeveloper documentation
404providers.credential_not_foundproviders

No such credential for this provider

Returned by the implementation; no specification rule declares it yet.

The credential id or reference does not name a credential on this provider.

Why the API refuses

no such credential for this provider

What to do

List the provider's credentials and use an id from the list. A revoked credential is still listed, with status: revoked — it is not missing.