You have a few options as noted below. Options 1 and 2 are short-term, while option 3 is considered the best option if you don't plan to reinstall the device (option 4).
If 2 or 3 did not work, ensure you have an up-to-date install of Docker, [refer to the official Docker docs for installation.](https://docs.docker.com/engine/install/debian/)
Use another tag, not based on Focal. At the time of writing we currently offer a `bionic` tag for [Plex](https://github.com/linuxserver/docker-plex) and [Jellyfin](https://github.com/linuxserver/docker-jellyfin) that will receive the same care as latest for the foreseeable future.
* 502 errors in __Jellyfin__ as seen in [linuxserver/docker-jellyfin#71](https://github.com/linuxserver/docker-jellyfin/issues/71)
*`Error starting framework core` messages in the docker log for __Plex__. [linuxserver/docker-plex#247](https://github.com/linuxserver/docker-plex/issues/247)
* No WebUI for __Radarr__, even though the container is running. [linuxserver/docker-radarr#118](https://github.com/linuxserver/docker-radarr/issues/118)
* Images based on our Nginx base-image(Nextcloud, SWAG, Nginx, etc.) fails to generate a certificate, with a message similar to `error getting time:crypto/asn1/a_time.c:330`