To troubleshoot why your laptop’s webcam isn’t showing up in device manager, please try the following:

1. Check if the driver is installed:
   Check if the right driver is installed and updated for your webcam device in the computer.


2. Verify Working Status of the Webcam:
   Verify if your laptop’s webcam is turned on and functioning properly by checking the light near to it (usually near to the lens) and by trying to access it using software or apps.


3. Re-Adjust Settings and Permissions:
   Make sure all the settings under system preferences and privacy settings demanding permissions for the camera are granted.


4. Perform a Hardware Troubleshoot:
   Disconnect the web cam, restart the computer, reconnect the web cam and check if the device is able to function properly.


5. Uninstall the Existing Web Cam Driver and Re-Install It:
   Uninstall the existing web cam driver and re-install it to check if the old driver was causing the issue.