Am I being crazy or paranoid?

Is there a good reason why my boyfriend clears his recent searches on his messenger app? (I’ve wondered before if he’s messaged other girls and I’ve even asked about it and he repeatedly tells me no). I did ask him why his recent searches are always cleared or why the same people don’t show up since the last time I looked at it, and he says he doesn’t do it so he doesn’t know why his searches get cleared. I’ve done some research about it and from what I’ve read, a person’s search history only gets cleared if they (1) delete the messenger app and reinstall it; (2) sign out of their messenger account and log back in; or (3) goes through security on their Facebook app.

Is there honestly another way where recent searches get cleared without the person doing it themselves? Or can it only be done by the person doing it.

Thanks in advance everyone!