[Q] Not booting after build.prop change topic

Hi

I have IUNI U3
I wanted it to support google services, so i've followed some guide from this forum
According to the guide, I had to change the ro.product.model
Since then, the phone is not starting..even not fastboot : /

I have a backup of the file inside the phone, but there are 2 main problems:
1. adb has issues connecting the device..
When I connect the device to the computer, it starts searching for drivers
During the search the device is connected, but when it fails, the adb sees the device as offline
Do you have any idea how can I get the drivers? I don't know chinese, so I have problems searching the official site

2. if I do manage to get inside with adb, it doesn't have permissions on the files

Please HELP : ///

Thanks