Huawei P Smart (FIG-LX1) Cameras won't work after screen replacement

Hello everyone

yesterday I was replacing a broken screen of a Huawei P Smart (FIG-LX1).

I bought the full replacement with frame because the latter was a little bit damaged too. The replacement process went smoothly (I used to work in a repair shop) without any kind of problem at all. I tested the LCD and touch before the re-assembly, I didn’t tested the camera to be honest, my mistake, so I ended closing the back cover and powering on the smartphone.

Everything was working except the cameras and the backlight. If I open the camera app, it crash, without any error or kinda. I know is not a software issue so I think that an hard reset will not fix that problem even if is the first suggestion that I found searching a workaround.

I can try placing back the old screen to check if then is working, but that means unglue the battery and all the stuff, and is very likely to don’t worth it. I’ve seen that for the iPhone usually the problem is the voltage regulator, it can be a similar problem?

What you suggest to do first?