Snapd error: system does not fully support snapd: cannot mount squashfs image using .... Operation not permitted. Ubuntu 20.04

Question

Im trying to install certbot and snapd core etc and it gives me this error:

error: system does not fully support snapd: cannot mount squashfs image using "squashfs": mount: /tmp/sanity-mountpoint-718641914: mount failed: Operation not permitted.

I have searched for so long and haven't found anything. If someone has a solution for this, please tell me.