How to Fix It
I’ve seen quite a few a few people talk about how raids aren’t working or are getting stuck. I had this problem 20 hours into the game, day 30 and level 25 and have never even seen a warning (even tho my raids were turned on).
I did a bit of testing to see why my raids weren’t even triggering. First my base was near an ocean where all the pink trees are next to a boss fight. I got nothing.
Then I started a new world and built in the same spot and still nothing. I thought maybe the issue was due to the multiplayer setting being on (I was turning it on even tho I was solo) and that did end up working but mind you I built my base near and behind the castle area on a beach by the spawn.
I didn’t like this spot so I tore it down and built myself on a flat area in the middle of the spawn island connected to a dirt path. And that also seemed to have worked.
So it seems like the raid AI Only triggers if it detects a base being built close or on a dirt path. (I say close because I built on a beach close to a dirt path and not on but they did get stuck which is why I moved).
TLDR: Raid AI seems to only trigger if you’re building on a dirt path or near one.