Try the suggestions in this Community Tip to help you fix ERR TOO MANY REDIRECTS.
If your SSL setting on the Crypto tab 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.
Quick Fix Ideas
Remove the HTTPS redirects in your origin server.
To ensure all requests between the browser and Cloudflare are encrypted, you can use an Always Use HTTPS page rule and that way avoid a redirect loop.
If you host a Wordpress site, read about potential issues with Flexible SSL.
Enable Full or Full (Strict) mode. Learn more about all the SSL options available through Cloudflare.
If You Need More Help
This community of other Cloudflare users may be able to assist you, if not, login to Cloudflare and then contact Cloudflare Support. When you contact support, make sure to include as much of this information as possible: Go here and send trace output from one of the affected devices, error messages, screen shots, and/or HAR file(s).
Expert Comments Appreciated
This Community Tip will remain open for input from Community experts and those familiar with this issue. We really appreciate comments that start with words like: “The three things I always try”, or “Do this first” or “In my experience”.