"Unable to save custom claim.: not primary" error

Problem statement

We are on the Converged Platform. The below error happened right before a user logged in successfully. This error happened only once. Can you help us understand this error?

error: server_error, error_description:Unable to save custom claim.: not primary


not primary is an error due to a change in the underlying datastore, likely to a change in writer nodes due to an underlying node failure - e.g. a hardware failure that causes another data replica to be used. While not a regular occurrence, these changes can occur and should not result in ongoing issues.