Bought a used phone on olx, when i factory reset the phone it has magisk manager installed and device status is custom in the about phone menu, meanwhile its on jan 1 2019 security patch android 9 and there is no software update option either. Model is 960F/DS dual sim variant, plus i had to install google play games and some google apps are just not downloading from the playstore like netflix,spotify etc saying app is incompatible with my phone. Imei is matching with the device details and it is pta registered on both sims, signals are tough to catch thou. Can i recover the phone to stock software ?