Hi,
Thank you for writing to Microsoft Community Forums.
We understand how difficult it could be. However, in order to get more clarity and assist you further, we would need some information regarding the issue.
- May I know the make and model of the computer?
- Do you face this issue during other scenario (apart from using screen mirroring)?
- Does the computer support Miracast?
- Has it ever worked?
- Was there any major change on your system prior to which you weren’t facing this issue?
We would also suggest you to refer Update drivers in Windows 10 and try updating graphic card driver and check if it resolves the issue.
You may also want to refer MIUI Wireless Display: Wirelessly Mirror your Smartphone Screen to PCs or TVs and Fix connections to wireless displays or docks for more details.
Regards.