Bro There are just two things left to do.

1st: try to boot into your firstboot then flash your update.img file(If you have taken backup ever before you will find it there, otherwise search for the stock rom of your device from the menufecturer company).

2nd: Turn off the phone then remove the bettary for about 2 minutes then renter the battery. Now press [Vul -] & Power button at once for about 10 seconds, you will be on your recovery(stock recovery or cwm or TWRP- I don’t know what you already did with your device).

Now restore factory settings from there. Remember you will loose everything including phone memories contacts. So try not to do this unless it’s the last option to take.

–It’s a pain to type on android so decided to go with english. Sorry for that.