Thank you for your question. I tested your subdomain, and it is pointed to cloudflare's IP addresses, and loading for me without 406 errors.
From what I read online, this may be caused by cloudflare being blacklisted due to their policy on abuse. Just like anywhere online, some people use their service to do things that it wasn't designed for.
Please feel free to contact us at any time if your issues persist. If you have any further questions, feel free to post them below.
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