From your comment, it appears that you have two different TeX live installations on your system, the system one in /usr/bin/updmap-sys, which probably was installed by your package manager, and a custom installation in /usr/local/texlive/2021/, which was probably installed manually.
The one in your system path is being searched first, but is out-of-date and only half-functional. You want to make sure that /usr/local/texlive/2021/bin/x86_64-linux appears in your PATH before /usr/bin. One way to do that is here.
You might additionally want to run
sudo -E $(kpsewhich texhash)
sudo -E $(kpsewhich updmap-sys) -enable Map=mtpro2.map
The sudo -E $(kpsewhich ...) might be necessary for the command to run with the correct search path and environment. Running texhash might be necessary for the updmap-sys command to find the map file in the file index. I usually also set
alias update-tex='sudo -E $(which tlmgr) update --self --all'
so that I can update my installation with the command update-tex.
You’ll also find the commands I use to install and update my TeX distro as the system user tex, not as root, which means that any install script I run at least doesn’t rootkit my machine. This involves passing the sudo command the additional flag -u tex, usually through an alias.
Pragmatically, though, an installation script running as the tex user can modify an executable that I frequently run as my user account, which can then read and alter all my user files. You might reasonably conclude that getting root is not what should concern us.
whereis updmap-sys, does it find the correct installation? On some systems (such as a custom TeX Live installation on Debian) you need to runsudo -E $(kpsewhich updmap-sys) -enable Map=mtpro2.map. This calls the correct version with and preserves your environment. – Davislor Feb 21 '22 at 04:17whereis updmap-sys:updmap-sys: /usr/bin/updmap-sys /usr/local/texlive/2021/bin/x86_64-linux/updmap-sys /usr/share/man/man1/updmap-sys.1.gz. – Alberto López Feb 21 '22 at 04:57