hi, Good question, my only advice is don't do anything to your phone, my phone just like yours. and its rooted I flashed it using lgup and I installed the MM 6.0 firmware, now phone has lot of software issues. errors are LG vpn has stopped, finger print and security menu completely dead and I cant even uninstall the program too phone restarted its self. now I cant downgrade to LP 5.1, I'm stuck. I gave to LG service center to repair it but that also did not work, they said after market alteration, now phone is not rooted and cant install kingroot because of security menu not function to make to tick for unknown sources. I contacted to seller too, no reply from the seller
any help to come out from this situation I appreciate lot, where do I can find the correct firmware? this is the file I download from the net WEB_H90021w_00_0921.kdz, there is no other variant file other than this, I searched weeks, any help I much appreciate lot. thanks