Can't dist-upgrade my droplet.

I have an old droplet that I’m trying to upgrade. I’m getting this:

root@ubuntu-s-2vcpu-4gb-nyc3-01:~# apt-get update
Ign:1 http://mirrors.digitalocean.com/ubuntu groovy InRelease
Hit:2 http://old-releases.ubuntu.com/ubuntu groovy-security InRelease
Ign:3 http://mirrors.digitalocean.com/ubuntu groovy-updates InRelease
Ign:4 http://mirrors.digitalocean.com/ubuntu groovy-backports InRelease
Err:5 http://mirrors.digitalocean.com/ubuntu groovy Release
  404  Not Found [IP: 104.21.29.13 80]
Err:6 http://mirrors.digitalocean.com/ubuntu groovy-updates Release
  404  Not Found [IP: 104.21.29.13 80]
Err:7 http://mirrors.digitalocean.com/ubuntu groovy-backports Release
  404  Not Found [IP: 104.21.29.13 80]
Reading package lists... Done
E: The repository 'http://mirrors.digitalocean.com/ubuntu groovy Release' no longer has a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://mirrors.digitalocean.com/ubuntu groovy-updates Release' no longer has a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
E: The repository 'http://mirrors.digitalocean.com/ubuntu groovy-backports Release' no longer has a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.
root@ubuntu-s-2vcpu-4gb-nyc3-01:~# apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following packages have been kept back:
  ubuntu-advantage-tools
0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.
root@ubuntu-s-2vcpu-4gb-nyc3-01:~# apt-get dist-upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
Calculating upgrade... Done
The following NEW packages will be installed:
  distro-info
The following packages will be upgraded:
  ubuntu-advantage-tools
1 upgraded, 1 newly installed, 0 to remove and 0 not upgraded.
Need to get 838 kB/855 kB of archives.
After this operation, 2979 kB of additional disk space will be used.
Do you want to continue? [Y/n] Y
Err:1 http://mirrors.digitalocean.com/ubuntu groovy-updates/main amd64 ubuntu-advantage-tools amd64 27.1~20.10.1
  404  Not Found [IP: 104.21.29.13 80]
E: Failed to fetch http://mirrors.digitalocean.com/ubuntu/pool/main/u/ubuntu-advantage-tools/ubuntu-advantage-tools_27.1~20.10.1_amd64.deb  404  Not Found [IP: 104.21.29.13 80]
E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing?
root@ubuntu-s-2vcpu-4gb-nyc3-01:~#

Note: It made me add a tag. The only one available was 20.04, but according to my droplet info it’s 20.10.