I am also experiencing this issue on my pc (Windows 11), and I have no mods or cc. The first week worked without any issue, so I claimed the first 5 rewards, but this week has the event greyed out with a "Please wait and try again as the Gnomes try to fix the failure" message listed. All the items I collected last week show uncollected in the event but unlocked within build mode. I've logged in and out of my game, rebooted, and tried a different day of the week but no luck so far.
Edit: I resolved this for my game by logging out of the EA client and signing back in. My event issue was resolved as soon as I loaded my game again.
5/27/26 Edit: The event was greyed out again today when I logged in, so I repeated the sign out and back into EA I did previously, then reloaded the game which resolved the issue once more. Seeing as the event is a log in based reward system, it makes me wonder if the 'Keep me signed in' client feature isn't conflicting with this event a bit.
5/28/26 Edit: Event was greyed out again, so I repeated the steps above which resolved it once more. I think I've confirmed it's tied to the EA client log in, so I turned that feature off.
5/29/26 Edit: Today I confirmed the event works properly for me if I manually sign into EA instead of using the 'Keep me signed in' client feature through sessions. I then repaired my game, and turned the 'Keep me signed in' setting back on, so I can see if this will resolve the daily error or continue with the same pattern.
5/30/26 Edit: The event was greyed out again with the 'keep me signed in' client feature turned back on. The game repair yesterday didn't fix that, so I've turned the setting back off for now as I'm fairly sure it's linked with my game event.