Hi Jordan,
Thank you for reaching out. The error "Failed to refresh access token" indicates that your refresh token is probably expired. There is likely an issue with your OAuth Credentials. Can you please try to generate a new set of credentials by following
this guide and see if that fixes the issue? If you are still having an issue, please provide the complete detailed request and response logs and the email address used to generate the credentials
via Reply privately to author so that I can further investigate the issue.
Regards,
Mitchell
Google Ads API Team

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