Unable to install on Linux Mint

I am trying to install on Linux Mint 20.1
Following the install instructions I get to sudo apt update. This fails:
E: The repository ‘https://apt.releases.hashicorp.com ulyssa Release’ does not have a Release file.
N: Updating from such a repository can’t be done securely, and is therefore disabled by default.

Hi,

I know the question is already here for months but I had the same problem and for Linux Mint 20.1 you should use this command:
sudo apt-add-repository “deb [arch=amd64] https://apt.releases.hashicorp.com focal
main”
instead of:
sudo apt-add-repository “deb [arch=amd64] https://apt.releases.hashicorp.com
$(lsb_release -cs) main”

lsb_release -cs doesn’t work in this case.
Explanation can be found here: Docker Repository Does Not Have a Release File on Running apt-get update on Ubuntu - Stack Overflow

If you have a different Mint version just change “focal” to the correct package base of your distribution.