Long story. It originally had CWM installed and custom rom. After many tries to install TWRP custom recovery with apps like Rashr, the phone ended up with no IMEI and no functioning recovery (It would black screen and restart if turned on in recovery).
After another try to flash recovery with SP Flash Tool ( i didn't even flash it, just struggled with windows 10 drivers ) it is now dead ( almost ). It just powers on ( vibrates ), screen turns on ( but no images ) and resets itself in a matter of 5-6 seconds. What should i do ? It sounds like a bootloader problem to me.
My last resource is to wait till battery drains and try flashing the whole phone again as described here : https://forum.hovatek.com/thread-286.html.