Syncing issues

Me and another person are currently trying to sync a project so that we can work on it as a collaboration. We’re currently using the source control in the unreal editor, but when we right-click on the files in the content browser, the sync button does not appear for either one of us. Is there something additional we have to do to get this button to appear? Everything else (adding, deleting, submitting, etc.) is working for us. Any help or advice is greatly appreciated!