I’ve been using Cloudflare for about 2 months without issue. All of a sudden my access to my wordpress login page was blocked. The (.com/wp-login.php) page wouldn’t load and I’d get a 524 error code timeout issue. I got around the problem by clearing cache and pausing Cloudflare. I’d like to figure out the root cause. Has anyone had this issue?
What was the error code shown to you?
Related to the 524 error, may I ask which of the troubleshooting steps from the below article have you tried already? 
Before moving to Cloudflare, was your Website working over HTTPS connection?
Does it work normally over HTTPS when Cloudflare is Pause?
May I ask what SSL option have you got selected under the SSL/TLS tab at Cloudflare dashboard for your domain ( Flexible, Full, Full Strict … )?
Any security plugin running at your WordPress instance?
Are you using Cloudflare APO for WordPress maybe?
Or some firewall is installed at your origin host/serer?
A post was split to a new topic: Some site elements blocked