VALIDATION_ERROR

Indicates there has been a validation error from either target server-client or hub-server (for example, Msisdn has not valid format).

Note that, while hub-server most validation errors reports them directly in form of bad-request some errors still pass through this flow.

Operation is retryable.

In case the validation error comes from target server-client then, the main target of this error is hub-server, where the error will be logged and tracked.