Yuphoria bricked and stuck in bootloop

My Android device YU Yuphoria is currently bricked and stuck in a bootloop. What I tried to do to cause this was that I first rooted the phone and installed TWRP. Then I installed Android Nougat on it, which was a success for the first few days but later got corrupted somehow. Now I'm stuck in a bootloop. Whenever I try to flash its stock ROM, it gives an error message "E: failed to mount". Infact, whatever I try to do in the Cynogen recovery mode, it gives this same error message. Can someone help me out of this?