I solved the problem by installing the official ubuntu installation image and thus removing the shipped ubuntu from Dell.
I have a new XPS 13 Plus 9320 shipped with Ubuntu 22.04 TLS. But my webcam does not work and did never work before. It's not working in any application. Tried the following already Contacted DELL chat but that's worthless support, just like the webcam.
XPS 13 plus 9320 webcam not working