Hi MM RAHMAN,
Thank you for reaching out Microsoft Community. We apologize for the inconvenience this may have caused.
By the way, did the issue happen after installing updates on your Surface device? This seems like a common issue since I had assisted 2 Community members who have the same problem with Windows Hello.
To initially troubleshoot this issue, I would like you to follow the following steps below.
Check UEFI Settings if Cameras are disabled
Press & hold the Shift Key and select "Restart" from the power options. Once "choose an option" screen appears, select Troubleshoot > Advance Options and UEFI/Firmware Settings > Restart > Choose Devices > Make sure the cameras are being enabled. Then, select Exit to restart your Surface.
If no changes after enabling cameras, to further troubleshoot the issue, please download thisin-place upgrade. Downloading the tool will re-install missing drivers and repair those that are corrupted . It won't delete files nor remove the applications you already installed. Just click the "Download Tool Now", run and install and click Next once you see "Upgrade This PC".
If this helps, please let our Community know by marking this post as an answer. Otherwise, don't hesitate to respond to this thread for further assistance.
Kind Regards,
Crest_Z