I had the same issue just a couple of minutes ago. It seemed the player was actively exploiting it, but I can't be certain about that. I had the mana to cast the exiled spells, but even when I tapped the lands manually, I couldn't cast them for the heightened mana-cost. Lost the match as a result. Also, I noticed that no owner- or controller-information is given after clicking on the exiled cards in my hand. It just sais that the spell can be cast and that its costs are heightened. The costs were stated/displayed correctly and were raised by two.
My opponent was using a legendary water/blue-card ("Tessa the Deep Dwelling", or something like that) to exile the spellcaster and then have it re-enter the battlefield each turn. In the end, my whole hand consisted of exiled spells which I was supposed to be able to cast at a heightened cost, but wasn't.
I had the same issue just a couple of minutes ago. It seemed the player was actively exploiting it, but I can't be certain about that. I had the mana to cast the exiled spells, but even when I tapped the lands manually, I couldn't cast them for the heightened mana-cost. Lost the match as a result. Also, I noticed that no owner- or controller-information is given after clicking on the exiled cards in my hand. It just sais that the spell can be cast and that its costs are heightened. The costs were stated/displayed correctly and were raised by two.
My opponent was using a legendary water/blue-card ("Tessa the Deep Dwelling", or something like that) to exile the spellcaster and then have it re-enter the battlefield each turn. In the end, my whole hand consisted of exiled spells which I was supposed to be able to cast at a heightened cost, but wasn't.