I deleted my OS in TWRP recovery, I've tried doing many things but none of them have worked. I tried flashing a stock kernel using fastboot, flashtool, using sony's flashtool Emma but all of them gave an error. My bootloader was unlocked and i think USB debugging was on but i can't be completely certain. And I'm not sure if the phone is charging or not because it's just stuck on the sony logo.The model is D6503. I'm pretty new to this stuff so i don't know what to do, if you need any more information i'll try to provide it as fast as i can. Thanks in advance.