It is normal for Cloudflare to display the redirect page for validating requests before redirecting traffic to the origin when the “I’m Under Attack” option is switched on. This is more like a challenge page or a queue to all the requests before the traffic is redirected to the origin.
As for the 524 error, all current Cloudflare services look operational. I suggest you contact Cloudflare support if you believe that the problem is from their end.