Hey there, thanks for reaching out and welcome to the Streamlit community! 
Sorry you’re running into this 403 Forbidden error on your deployed app—this is a common issue and can be super frustrating, especially when everything works fine locally. The error you’re seeing (“Error 403 Forbidden” with Fastly/Varnish details) means your Streamlit Community Cloud account or app URL has likely been blocked, either due to exceeding fair-use/resource limits or being mistakenly flagged by the CDN/firewall. This can happen if your app triggers automated protections (e.g., by making frequent external requests or appearing bot-like), or if there’s a false positive in Streamlit’s monitoring system.
To resolve this, you’ll need to open a support ticket with Streamlit/Snowflake and include your GitHub username and app details. The support team will review your case and can unblock your account or app if appropriate. You can find the step-by-step process in the official docs: How to submit a support case for Streamlit Community Cloud and Login attempt to Streamlit Community Cloud fails with error 403. This is the recommended and fastest way to get your app back online. If you have a minimum reproducible example or more logs, please share them in your support request or here for community input!
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