I tried to connect a physical keyboard to my A7 pro and there was no reaction from the phone. It's a keyboard made for android phones and tablets with a micro USB connector. The keyboard works fine with other android phones. 
I also tried to connect a USB flash drive to the phone with a USB to micro USB adapter and also had no reaction. It works on other android phones.
Tried rebooting the phone, tried to install usb drivers on the phone, but had no results. Can someone help me please?

are you using the OTG usb cable? otherwise nothing will work!

for the flash drive i am using the OTG cable, but the keyboard has a cord with micro usb plug so i dont need the OTG cable for the keyboard

atty2005 wrote:

for the flash drive i am using the OTG cable, but the keyboard has a cord with micro usb plug so i dont need the OTG cable for the keyboard

You'll have to use the OTG cable anyway!