How to use mmctl Commands in Mattermost?

Something prevents you from using the terminal inside the app.

OCI runtime exec failed: exec failed: unable to start container process: exec: “/bin/sh”: stat /bin/sh: no such file or directory: unknown

I am trying to run the command to delete a user. From how I understand it, that only works through the terminal.

I also tried to ssh into the server on the two ports it publishes as well as ssh port. Connection was always refused.

Anyone?