Help needed Migrating on prem VSTS2018 GIT repo into Azure DevOps repo

I could use some direction migrating on prem TFS 2018 server with GIT repos into our orgs Azure DevOps repo. I have tried using the import repo option in DevOps but get the Clone URL is incorrect and the Clone URL requires authentication.  I did create a PAT token for this as well (suggested from stack overflow) but its not working either. Am I trying to do something that is not supported?? 

Craig