403 problem with meta ads (instagram)

Title: facebookexternalhit gets 403 on my custom domain — looks like platform-level mitigation (Hobby)

Hi, Meta's Sharing Debugger consistently returns 403 for https://www.michaelfx-community.co.uk with the "could be due to a robots.txt block" message.

www.michaelfx-community.co.uk

MichaelFx Army — Trading Signals & Community

Join MichaelFx Army: live trading signals, a private Telegram community, and educational content to sharpen your trading.

What I've already checked:

robots.txt allows everything and explicitly allows facebookexternalhit, Facebot and meta-externalagent
Bot Protection is Off, AI Bots set to Allow, Attack Mode is off
Custom firewall rules "User Agent contains facebookexternalhit → Bypass" are live — Meta still gets 403
The site loads fine in browsers and returns 200 to other fetchers
Other projects on my account scrape fine in the Sharing Debugger — only this domain is affected

This matches recent threads where Meta's crawler (AS32934) is blocked by platform-level DDoS mitigation before reaching the project firewall. I'm on Hobby, so I can't add System Bypass rules.

Could someone from the team check the platform-level mitigation for michaelfx-community.co.uk and exclude Meta's crawler? I'm running Facebook ads to this domain, so it's fairly urgent. Thanks!

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