I'm back with more Archipelago issues, I'm sorry!

I don't think I can play without Archipelago now, so the fact it's currently not working is deeply distressing.

I'm playing a solo game, no mods aside from Archipelago and SMAPI, so I have no idea what's causing the issue. I'm trying to start a new game and getting a SMAPI error saying "[StardewArchipelago] An item with the same key has already been added. Key: 721107"

There's nothing else running that could be clashing with it, this is a brand new save that I can't even start day 1 on because it gets stuck trying to open, I assume due to that message. I've uninstalled and reinstalled both SMAPI and Archipelago, that didn't fix the problem. I can't find the key anywhere to see what the problem actually is, but I know from SMAPI experience that this error message usually means two mods are clashing, but there are no other mods for it to be having problems with.

If anyone has any ideas on what the problem is or how to fix it, I'd be very grateful! Thank you!