https://support.cloudflare.com/hc/en-us/articles/203118044#h_b8cebafd-9243-40e9-9c44-d4b94ccd3a87
Run the trace command as suggested in the error
- Open the Network Utility application.
- Click the Traceroute tab.
- Type the domain or IP address in the appropriate input field and press Trace .
- You can copy the results to save in a file or paste in another program.
Or from a command line, `$ www.mindymakes.com/cdn-cgi/trace
I get a 521 on https://mindymakes.com/ and was getting a bluehost place holder page (as if there was no site content to be loaded) on www.mindymakes.com although now I am getting a 521. I’d contact bluehost and find out what’s going on with your origin server, 521 and 503 both indicate some origin issue.
Did you make any changes on your site just before it stopped working?