Blue crystal

Played for 5 months, fought off enemies with some difficulty (although without antimagic – by the way, it’s not even in the tome of light magic) and finally reached the prophet. Found everything he asked for, and then some strange thing happens. He takes the boots and the rune, but for some reason, the dust doesn’t suit him, and he doesn’t take the resources. If I try again, he asks me not to bother him. What kind of nonsense is this? Is this a bug? I tried to go into the treasure room, but it’s already empty. It’s a complicated situation, what should I do?