After completing a 5* dungeon, i did not receive my reward.

What i think is causing this bug:
The level of your class must be high enough to be granted to get reward(s) from 5* dungeon(s)

You need to be level 25 to unlock your first Cosmic Gem Slot, which i think is what is the problem.

I am lvl27 on my CB and can receive my reward.
But on my Neon Ninja i am lvl23 and i was not receiving my reward.

See video: