Jenkins not cloning

I am setting up a Jenkins build that uses a GitLab repro. I have set the SCM Git to the GitLab url but Jenkins is not cloning the repro. It tries to fetch the repo but it is not there because it was not cloned. Is there a step in Jenkins that tell it to clone the repro before trying to fetch it?

What type of job are you running? Is it Pipeline, Multibranch Pipeline, Freestyle, or something else?

What URL did you enter? When I enter the URL as if fetches the remote repository and performs a checkout without any issue.

What message is in the Jenkins build log that leads you to believe that the repository has not been fetched (since the Jenkins git client plugin never uses git clone, it always uses git fetch)?

What are the contents of the workspace where the git fetch was performed? Does it contain a .git directory?

Command line git can fetch repositories without cloning them first. The git plugin relies on that capability. What did you observe that persuades you that the repository is not on the agent? Is the directory empty except for a .git directory? Is the directory completely empty?

Much more information is needed before others can help you with your question.