Drowned not attacking me

Once I made a survival world in Bedrock Edition and found a village. I had the add-on "Village Guards" installed, which replaces wither skeletons with village guards, but I don't think it is responsible for this bug since it doesn't affect Drowned. The village was next to a swamp with a witch hut in it, and as I was approaching the witch hut, I saw a Drowned on an island, so I went over to kill it. It was daytime and the Drowned was under a tree, but when I approached it, it stayed where it was. I walked right up to it and it didn't attack until I was right in its face. But when I moved backwards again, it didn't follow me. So I punched it to push it into the water and it immediately regained its AI. I have heard that Drowned become passive during day if the way to water is blocked, but the way to water was definitely not blocked on that island. Is there a bug with the Drowned AI, or is it the Add-on's fault?