Are these new notifications you have gotten? Or are they old notifications that now have broken links? It's possible that older notifications that are hanging around in your inbox are lacking all the information that we now include with notifications, so there could be broken links from that.
It looks like blahaj is running a very recent build of the code, so if these are new notifications, it must be something else. It doesn't look like you are a moderator or admin, so you shouldn't be getting reports as notifications. It could be that somewhere in the code it is sending the wrong notification type. There isn't too much else I can help with without getting some lower level information.
@rimu@piefed.social - It would be really helpful tracking this down to figure out what type of notification these are saved in the db as and any other targets
saved along with them. A quick search in the code and I don't see any type 20 or 40 notifications where they shouldn't be.