Problem with pairing device using wifi in android studio

I want to pair my android device by scanning QrCode in device manager android studio.

Sometime it works but often it doesn't work.

when I scan QrCode it waits in state below

I try ways below:

1- Connecting to same wifi

2- Deleting all previous paired devices

3- Try to connect using pairing with code

4- Reseting android studio

and all solutions offered in stack

By following the 7 steps below, your problem will be solved definitely:

1. You should add adb to your environment variables. open your environment variable and add Your-SDK=path\platform-tools to environment variables Path.
2. In your device open Wireless debugging under developer options.(if developer options not exists in your settings you should activate developer mode)
3. in wireless debugging tap on Pair device with pairing code.
4. in your Android studio open Terminal and write commands below in terminal.
5. adb pair Ip-address:port (get Ip address from dialog below)

6. Insert wifi pairing code. (get pairing code from dialog above)
7. adb connect IP-address:port (get Ip address & port from dialog below). You've done successfully. congratulations