In retinue card Handbook, League of Goddess, the Exchange buttons of both Luia and Tia are not active (I can't click them), despite I have both as buddies, so I can't exchange them. I can, however, do the exchange for other goddesses I have not even encountered yet, like Hathor. Right now I don't have enough shards to do it, but this is about the buttons not being clickeable.
I have the same problem in retinue card handbook, Power of Angel section, all buttons are active except for Archangel and True Lisa, and I do have True Lisa in my team.
Is this a bug? Can be fixed?