You should be able to see the challenged or blocked event under the Security tab → Events at Cloudflare dashboard for your zone and know exactly which security option was triggered.
Once you find them, click on a particular one to find more details about it (user-agent, IP, HTTP version …). If yes, could you share some details which service was triggered that blocked you?
Otherwise, If you get this error while visiting someone else’s website, I am afraid you cannot do anything. You can try to access it using a VPN or over a TOR, but I do not guarantee because it could also be blocked and restricted.
Obviously the website owner is using Cloudflare and security options available to him to protect his website.
Maybe you have had some bad requests, or the owner decided to deny the requests comming from your country, etc.
The site can block for any number of reason, that’s up to them and not something this Community nor Cloudflare can do anything about.
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