I’ve tried clearing the data on every single wallpaper-related app (including system apps) that I can find. Galaxy Themes has long been disabled on my phone. The only thing I haven’t tried is a factory reset, because doing so is time consuming and I have a lot on my phone that I would have to backup/replace, including lots of app data that I don’t want to risk losing, and I don’t like the hassle of re-entering my credentials into every app. Is there anything else I can do?
I have the Pokemon Go PvP update loading screen as my background, and set it when the update came out in January 2020. Ever since, whenever I’ve tried to change my wallpaper to something else, it ultimately, eventually reverts back to the Pokemon Go wallpaper. It seems to revert when my phone suddenly lags when using/opening an app. For example, I tried setting my wallpaper to something else yesterday, and it stayed with the new wallpaper for most of the day. Then, I opened Pokemon Go, and it suddenly started freezing. I hit the home button to close the app and restart it, which also took some time and lagged a bit. When I got to the home screen, sure enough, the wallpaper had reverted again. The wallpaper isn’t even on my phone anymore, as far as I can tell. I’ve long since deleted it from my photos, as well as the trash. I’ve used file explorers to look deeper, and haven’t found it anywhere, and yet it somehow is able to be my phone’s homescreen wallpaper.