Middleman cli error - ` Could not locate Gemfile or .bundle/ directory`

I’m trying to use Middleman on Mac, first installing it by doing:
gem install middleman

Which works fine, but when I do middleman init my_project or middleman version I get the error message:
Could not locate Gemfile or .bundle/ directory

Middlemac assumes that you are using Ruby Version Manager (RVM) when you install it. I suggest you install RVM and try again. I recently installed Middlemac on a new Mac Mini M1 having installed RVM first and had no problems.