Error 525: Why is it happening?

I have got this error with Cloudflare. Why is this happening?

Hey hello I checked the ssl certificate of your site and it is valid, same for the SNI it is well configured. The error that may be there and that your site is supported on an unsecured Cloudflare port (http).

HTTPS ports supported by Cloudflare:

  • 443
  • 2053
  • 2083
  • 2087
  • 2096
  • 8443

I do not think that the error can come from encryption because I use the “strict” protocol and my site works perfectly.