I started the reaper's rewards and completed all of Week 1 "Assistant to the Grim Reaper" but there was an issue with "A Call Away".
I had gotten the ambrosia newsletter and read it but then I guess there was some sort of bug where a whole bunch of Discovery Quests showed up at once and when I completed those the "A Call Away" Reaper Rewards was no longer interactable.
I've tried started a new game, removing all mods, resetting Discovery quests, renaming my sims 4 folder, and removing (and eventually re-adding) my sims 4 folder, but nothing fixed it or even restarted the reaper rewards.