thank you for answering my firmware is:

Android 5.1
BV5000_c1_Blackview_V0.3_20151225
Kernel 3.10.65+

Best regards,

after the 'upgrade the back room does not work and the front and' upside down. I've seen other forum posts but have not given any valid solution. While doing the cleaning and resetting the phone and not 'served has nothing. Can you arrange to make a solution to this problem that not only affects me?...

after the 'upgrade the back room does not work and the front and' upside down. I've seen other forum posts but have not given any valid solution. While doing the cleaning and resetting the phone and not 'served has nothing. Can you arrange to make a solution to this problem that not only affects me?...