Is this a bug? I can only get the first kill task from him, he just gives the same finished one over and over?
One possibility . . . Perhaps your pop-up offering the quest is smushed around to only see the first line offered? Try stretching out the different sections of the window to see if you can see a longer list of available quests.
Nope tried that made the window windows size, only the one is offered. I tried accepting that one and dropping it a few times.
Ok I see even though one task was showing the other was indeed squished!! https://pasteboard.co/IH8kdNP.png