If your webcam is displaying a black screen, check the following:
1. The slider in the centre of the lid just above the laptop screen is in the on position.
2. Do you have the latest version of Teams installed? Check by clicking on the three dots in the top right-hand corner and select Check for updates.
You can also check if there are any Windows updates or Dell system updates pending?
You should be able to run the Dell SupportAssist app to check for system/driver updates. If you don't have the app, you can download and install it from the Dell UK Support web site: https://www.dell.com/support/contents/en-uk/article/product-support/self-support-knowledgebase/software-and-downloads/supportassist
Launch the SupportAssist app to check for system updates. If any are found, proceed with installation with the exception of a BIOS update as this will require IT assistance.