In that case it’s best to contact Cloudflare support to sort that out.
To contact Cloudflare Customer Support, login & go to https://dash.cloudflare.com/?account=support and select get more help. If you receive an automatic response that does not help resolve your issue, reply and indicate that you still require assistance. And, please share your ticket number here so that we can track it. @mianmian
Also,
I would recommend you to go for Full (strict). Nothing to do with the Error 524, but this can further improve your security.