Hi acer 15,
Since WhatsApp audio calls still work, the issue appears to be limited to camera access or the WhatsApp app itself.
Please open Start > Camera and check whether the camera preview works there. If it does, fully close any other apps that may be using the camera, then update WhatsApp through the Microsoft Store. You can also go to Settings > Apps > Installed apps > WhatsApp > Advanced options, select Repair, and test again. If Repair does not help, select Reset or reinstall WhatsApp.
If the camera does not work in the Windows Camera app either, run the camera troubleshooter in Get Help and install any available Windows and Surface driver updates.
Could you also let me know what happens when you start a WhatsApp video call, such as whether the video button is unavailable, the screen remains black, or an error message appears? Thank you so much for your understanding.
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