huawei mate 7 stuck on logo after lcd replacement and red light flash

I have a Huawei mate 7 wich needed a new lcd. I did the dissasembly the whole phone to replace the lcd. It seemed that everything went ok, but when i cloed the phone and tried to power on it did not turn on, I put it in charge but the red light began to flicker and it shows me the red battery sign. I tried to unplug the battery and plug directly to the charger, the red light flashes again and the phone boots up but restarts intermittently and as soon as i plug the battery it again shows me the red battery sign.

I really do not know what to do.