I was just experiencing something similar. Although the issue OP describes is the push continuing to sync but failing to connect, in what sounds like an initial commit. In my case it appeared as though all pushes were successful, in an existing repo/project where I've never had issues, nor had to do any initial git configurations inside VS... Things have always just worked, until the past few days, I just noticed none of my pushes actually made it to the repo.
But the title of the post is still relevant, so I'll answer in case it helps anyone else:
A simple VS Code update fixed my issue. While troubleshooting, I noticed a notification on the gear icon in the bottom left - which was an update ready to install. Once the update was installed and VS code restarted, I tried another pull, and then a push and everything's back to normal. Three commits finally found their way to the repo.