ipad still indicating that website is “Not Secure”

My website is proxied behind Cloudflare and - when accessed from various computers - this appears to be working as expected. (Nice!)

Also, if I connect to my website from my iPad by typing the URL into Safari, it goes to https://example.com - as expected.

However, I noticed yesterday that if I connect to my website via the link in an icon on the ipad’s homescreen it still goes to http://example.com and still says “Not Secure”.

Why is this happening? and how is it even possible?

(The actual IP address is not the same as it was before going with Cloudflare.)