Problem with youtube-dl Ubuntu 20.04

Update it to the latest version with

sudo youtube-dl --update

and then try again.

Edit: Since you wrote you installed it with a package manager and thus you can't update it so easily, for this particular software I'd recommend to install it from its upstream site https://youtube-dl.org/ to your /usr/local/bin directory and use it from there; then you can update it whenever needed (which is often because YouTube often changes some stuff to thwart software like youtube-dl).

You can either have a version from an official repo which is always slightly outdated, or a working one. As a general rule of thumb, you need to update it whenever you want to use it.

I just updated it, and it gives me

sh@balrog:~$ youtube-dl --version
2021.04.01

The problem seems to have been resolved by updating via pip3 command. It seems I needed a restart ... sorry, I'm a newbie and this is a newbie mistake: "have you tried turning it on and off". I'm happy to leave the question here for other newbie's, but otherwise don't mind if removed..