If enabling your default setup is taking too long, try canceling the workflow run and restarting the configuration process.
To restart your configuration, navigate to the main page of your repository, then click Actions. Click the CodeQL workflow run that's in progress, then click Cancel workflow. Once appears beside the workflow run name, navigate back to the Code security and analysis settings and re-enable default setup. If default setup continues to stall, please contact GitHub Support or try enabling advanced setup. For more information, see "Configuring advanced setup for code scanning."

