Zoom silently invalidated API credentials

It looks like Zoom has silently revoked our Meeting SDK credentials. Attempting to use the credentials as they appear on the control panel results in MobileRTCAuthError_KeyOrSecretWrong. Current builds of our app worked fine until yesterday.
Simply changing the credentials to different ones under a different account is enough to ‘resolve’ the problem. However, ideally the credentials listed on this account should work.