Page caching seems not working for both dynamic and static pages

I’ve signed up for Cloudflare, and copied over the API key and my email address, but when I “test cache” I get this error:

Page caching seems not working for both dynamic and static pages.

Error on dynamic page (https://advancedinstitute.ai): Seem that your website is not behind Cloudflare. If you have recently enabled the cache or it is your first test, wait about 30 seconds and try again because the changes take a few seconds for Cloudflare to propagate them on the web. If the error persists, request support for a detailed check.

Error on static resource (https://advancedinstitute.ai/wp-content/plugins/wp-cloudflare-page-cache/assets/testcache.html): Seem that your website is not behind Cloudflare. If you have recently enabled the cache or it is your first test, wait about 30 seconds and try again because the changes take a few seconds for Cloudflare to propagate them on the web. If the error persists, request support for a detailed check.

Please check if the page caching is working by yourself by surfing the website in incognito mode 'cause sometimes Cloudflare bypass the cache for cURL requests. Reload a page two or three times. If you see the response header **cf-cache-status: HIT** , the page caching is working well.

To avoid a “fake negative” from ** WP Cloudflare Super Page Cache**, I tried to check the headers from chrome inspection panel:

Response Headers:
HTTP/1.1 200 OK
Date: Mon, 20 Dec 2021 01:59:11 GMT
Server: Apache/2.4.29 (Ubuntu)
X-Frame-Options: SAMEORIGIN
Link: <https://advancedinstitute.ai/wp-json/>; rel="https://api.w.org/"
Link: <https://advancedinstitute.ai/wp-json/wp/v2/pages/1770>; rel="alternate"; type="application/json"
Link: <https://advancedinstitute.ai/>; rel=shortlink
Cache-Control: s-maxage=31536000, max-age=60
X-WP-CF-Super-Cache: cache
X-WP-CF-Super-Cache-Active: 1
X-WP-CF-Super-Cache-Cache-Control: s-maxage=31536000, max-age=60
X-WP-CF-Super-Cache-Cookies-Bypass: swfpc-feature-not-enabled
Vary: Accept-Encoding
Content-Encoding: gzip
Strict-Transport-Security: max-age=31536000; includeSubDomains; preload
X-XSS-Protection: 1; mode=block
X-Content-Type-Options: nosniff
Content-Length: 40034
Keep-Alive: timeout=5, max=100
Connection: Keep-Alive
Content-Type: text/html; charset=UTF-8

I also tried to activate “Overwrite the cache-control header for WordPress’s pages using web server rules” and the cache still not working =/

Could someone help me solve this problem?

The page I need help with: [log in to see the link]