I had the same/a similar issue and it turned out my laptop didn't like the kernel version. I made this post where I was helped and the problem was solved: Laptop with Zorin 16 doesn't shut down or sleep - #28 by UselessBoi
Basically I just installed the 5.11.0-40-generic kernel and set it to be the default version to boot into using Grub Customizer. You can try that if you want and see if that fixes your problem