I was playing in the qualifier weekend event, and I think I found a bug which made me lost a match.

I had a Vivi with a +1/1 counter and a voldaren thrillseeker exiled with Agatha’s cauldron. The opponent played a removal in my Vivi at the end of my turn, with me tapped out. However, Vivi’s ability to generate mana should be allowed to be used in my end step (I would generate a mana and sac them with the Voldaren exiled with the cauldron. It made me lose that game, since I couldn’t remove his creature in response. (See picture 2 - the 2/1 merfolk should be dead if I could sac vivi at the end of my turn if allowed to generate mana with them).

So, I’m asking to revert that loss if possible. If not I would please ask to allow me to play in day 2, or allow me to play in a future qualifier weekend.