When clicking the testing button I get

Hi I’ve installed the plugin, added the keys from cloudflare, everything seems to be fine. When I click the test button, I get this error:

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

Error on dynamic page (https://www.wonderlawnfranchise.co.uk): 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://www.wonderlawnfranchise.co.uk/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.

How do I check if the page cacheing is working?

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