Player cannot Mega Evolve if AI does so on the same turn

[Exodrake]

If the AI and I both Mega Evolve on the same turn, the NPC will mega evolve but I will be rendered unable to mega evolve for the rest of the battle, but the button stays, and I can still activate it by pressing start. but no mega evolution happens.

[Touched]

I am unable to reproduce this. Does this still occur with the latest code?

[Exodrake]

I'll check, but it only sometimes happens.