Subclass Skill Certification:
You have already received the certificate for this occupation.
I cannot give you any more certificates for your current occupation. If you wish to obtain another certificate, please come back as an occupation from another slot.
However, Ertheia are still connected to gods. So it would be meaningless for them to start a new life as a subclass, which also means that subclass certificates are meaningless for them.
(Ertheia cannot add a subclass or get a subclass certificate.)