Stuck on Infinite Hunger quest

I have "The Eater of Worlds" quest which tells me to pursue the Eater of Worlds' influence in tier 11+ maps which is fine. I complete the map with Eater of Worlds' influence on it and it gives me a Writhing Invitation and tells me to kill Infinite Hunger but when I do it doesn't complete the quest; instead it tells me to go pursue him in t11+ maps again and the Writhing Invitation drops after 1 map and tells me to go kill Infinite Hunger and the process repeats. I can't complete Eater of Worlds at all and cannot progress my atlas as a result.

same problem here. stuck on t11+ influence part of the quest. killed him 20 times, envoy doesn't show up after killing him.