When you open any static page of your e-commerce store, it may show the page is insecure even if the SSL certificate is installed successfully. This issue may happen due to the mix match of HTTP and HTTPS. In simple words, you are facing this issue because your page has elements which are serving HTTP location.
Suppose, you are facing this error on the product page of your ecommerce store. This might be due to the reason that your page is serving product image links from an HTTP location as opposed to HTTPS. For example if the image used in your page is causing the issue, then the image tag on your product page will look like:
<img src="http://sample-image.com/images/image.jpg"> and to fix this issue, follow these steps:
To know more about fixing HTTPS do not work on the static page of your site, go to the helpcenter - https://help.storehippo.com/topic/why-https-not-work-on-the-product-page