This could be caused by wrongly selected SSL options in SSL/TLS tab at Cloudflare dashboard, usually the
Flexible SSL option?
The connection between your visitor and Cloudflare is secured, but the connection between Cloudflare and your server is not. You will not need a certificate on your server for this mode. This option is NOT RECOMMENDED.
Flexible makes your site only partially secure - it encrypts the connection between the visitor and Cloudflare - this means they see the
in their browser and the site leaves the impression to be secure! However the connection between Cloudflare and your origin se…
Try the suggestions in this Community Tip to help you fix ERR TOO MANY REDIRECTS.
If your SSL setting on the SSL/TLS app is Flexible and if your origin server is configured to redirect HTTP requests to HTTPS, server responses back to Cloudflare are encrypted. Since Cloudflare is expecting HTTP traffic, it keeps resending the same request, resulting in a redirect loop. This causes browsers to display “The page isn’t redirecting properly” or “ERR_TOO_MANY_REDIRECTS” errors.
Therefore, it may be a sign that your origin host/server does not have a valid and a properly installed SSL certificate which covers your naked domain and www (and some other sub-domains too).
I am not familiar with 552, rather you mean on 525 error?
If so, kindly, to not repeat myself here again, may I suggest looking into the below post to find a solution for your issue which covers all the needed steps
May I ask what is your domain name?
Due to this error, obviously you are having a situation where:
The origin host for your domain does not work over HTTPS
The SSL certificate is not being installed or is not a valid one for your domain
Wrong SSL option being selected in Cloudflare dashboard on SSL/TLS tab
Possible use of a port for your app on your domain which is not compatible and supported with Cloudflare while using
cloud (proxy mode) for that hostname (DNS record)