Devious Cover-Up + Flip Cards [Investigating]

Abracadavers

I had a Sage of Ancient Lore in my had as the first card with some, but less than 9 mana in it.  On my opponent's turn they cast Devious Cover-Up and the Sage disappeared from hand (as expected).  On their following turn, they cast a Werewolf of Ancient Hunger (the flip side of Sage of Ancient Lore), which shouldn't be possible.

/Edited title - Daiane 

Magic:PQ Support Team

Hi @Abracadavers, 

Thank you for report! 
We will check it.