Wizard – “Haven” [Campaign 6, Mission 4]

Dear Experts, I can't progress, please help: I defeated everyone, I defeated Isabel, they are all together (Faydeen, Godric, Zahir), Zahir tries to perform the Ritual, a Demon appears, takes Isabel to Shio, Zahir takes the "Heart of the Griffin," and they ask him, "can we get them back?", Zahir answers "Yes," and that's it, the game freezes. I gathered all three together, I captured everything, all the cities, etc. What should I do?