VLC and gstreamer does not work

I’ve tried the Hello AI world setup and tried to check whether the camera is working. I transmit an rtp stream using the code taught in the setup video. After it works, I am supposed to use gstreamer or vlc media player to display the camera.
When I tried to use gstreamer, I ran the code in my ubuntu 18.04 LTS app in windows and it shows “ERROR: pipeline could not be constructed: no element “udpsrc”.”
When I tried to use vlc, I created an sdp file and using the code in the Hello AI World Github. I tried changing 1234 to 0002 ( port I am using) but it still doesn’t work.

The udpsrc plugin is in good-plugin package:

Please install the package and try again.

And cleaning cache may help:

$ rm .cache/gstreamer-1.0/registry.aarch64.bin