engineer mode

Hi, I live in Spain and I have problems with my phone bands, indoors I can not talk to the phone, and I have not 4G only H or H+, coverage while my Huawei P8 and another phones, yes. Solution? enter engineer mode *#*#3646633#*#* and "Bandmode" to change the bands most suitable for my country...

Hello everyone I've been tinkering in the engineer mode and would like to restore it to the original values that come by default , since I have touched the proximity sensor and not know how to return it to its starting point. I have tried restoring the phone making a factory reset but I see...