qt plugin error

I am getting this issue whenever I run the face recognition webcam demo command:

qt.qpa.xcb: could not connect to display
qt.qpa.plugin: Could not load the Qt platform plugin "xcb" in "/usr/local/lib/python3.11/dist-packages/cv2/qt/plugins" even though it was found.
This application failed to start because no Qt platform plugin could be initialized. Reinstalling the application may fix this problem.

Available platform plugins are: xcb (from /usr/local/lib/python3.11/dist-packages/cv2/qt/plugins), xcb.

I have this issue now for 10 hours and cant fix it please help me.

Start by reproducing the face recognition webcam demo command and inspect the reported cv2 Qt plugin path and display connection. Compare the runtime environment with the repository's Python SDK setup; done means the demo starts without the Qt xcb initialization error.

Written by the indexing model from the issue text.