Hi! I've encountered a recent issue with my ZTE phone. Whenever i try to install a new app, it'll download the app, but will get stuck installing it. It'll install for about 12 hours before i finally cancel it. I've tried going in to clear the cache and app data from the play store app, but it will just keep saying "calculating" and won't give me the ability to. I've only had the phone for a month. I also can't place large apps (like pokemon go and skype) on my SD card, although the card is very empty. The only things that i can think that might have caused this, was the fact that it forced a restart and update while i was installing a few apps. I've also downgraded some apps i didn't need to their factory version, but i don't know if that would affect anything. 

Any information would be very helpful, thank you!