Using git over HTTPS (instead of SSH) can sometimes be more likely to work on a locked down internet connection, such as on an airplane.

$ git remote add origin_https
$ git remote -v
origin (fetch)
origin (push)
origin_https (fetch)
origin_https (push)
$ git pull origin_https master

You’ll need a token for pulling if it’s a private repo. See Creating a personal access token for the command line at GitHub Help. You can also cache your GitHub password.