How does checkmate work in Spell chess?

Hi,

Somehow my opponent managed checkmate me with his last move e6, without me even being in check. Is this me not knowing how the check mate rules work in Spell chess, or is this a bug?

This is the game: www.chess.com/variants/spell-chess/game/53684341

Just my guess: Because I did a freeze on his king and my check mating pieces on my last move, the game (correctly) didn't register the mate. But since he couldn't get out of it anyway, it was still mate when it was my turn again. At that point, the last move registered was his move, and the game is in a check mate position, so the game thought it was his check mate

I had the same bug

https://www.chess.com/variants/spell-chess/game/53673619

I hope they just change the rules so that the game ends with king capture like in some of the other variants.