Your site is loading resources over an insecure connection. Modern browsers display a "Not Secure" warning in the address bar, which significantly damages visitor trust and can cause people to leave without converting.
On WordPress
Install the "Really Simple SSL" plugin — it scans and fixes mixed content issues automatically. Also run a search-replace in the database from "http://yoursite.com" to "https://yoursite.com" using the Better Search Replace plugin.
On Shopify
Shopify forces HTTPS automatically. Mixed content issues on Shopify are usually caused by content entered in the rich text editor with HTTP image URLs. Edit the content and update any HTTP image URLs to HTTPS.
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