ADB Device not found

[ x ] I have read the [FAQ](https://github.com/Genymobile/scrcpy/blob/master/FAQ.md).
[ x ] I have searched in existing [issues](https://github.com/Genymobile/scrcpy/issues).

Environment

OS: Windows 10
scrcpy version: 2.1.1
installation method: unzip-ed zip download
device model: Huawei Y9s
Android version: 10

Describe the bug

scrcpy suddenly stopped working. A few days ago it was working as intended but now it won't open. It launches and then closes immediately. This is what pops up:

`scrcpy 2.1.1
ERROR: Could not find any ADB device
ERROR: Server connection failed
Press any key to continue . . .`

thanks to anyone who responds! pretty new to this stuff, so any help would do!

Start by reproducing the failure with scrcpy 2.1.1 on Windows 10 and the Huawei Y9s running Android 10. Check why the ADB device is not detected; done means the device is found and scrcpy remains open instead of reporting server connection failure.

Written by the indexing model from the issue text.