GitLab CI build fails with git is not recognized

I have set up a GitLab pipeline, and configured a runner. The build starts when I make a commit, but fails almost immediately with the following message:

C:\GitLabRunner\builds\xxxxxxxx\0\cmac\portal>"git" "checkout" "-f" "-q" 

 '"git"' is not recognized as an internal or external command,
   operable program or batch file.

C:\GitLabRunner>IF 9009 NEQ 0 exit /b 9009 
ERROR: Job failed: exit status 9009

This is my .gitlab-ci.yml, which I have stripped right back to try and isolate the issue:

 - build
  CI_DEBUG_TRACE: "true"
  stage: build
     - Echo OK

The only similar issues I could find are here and here

I thought I had fixed the issue when I was getting the same message in a when trying to use git in a standard command prompt as my PATH wasn’t set correctly in Environment variables.

However I have now fixed this and I am getting expected responses back from git through the command prompt, however I still get the issue when gitlab kicks off the build.

Any ideas?