Requesting Insecure Resources

Hello. I’m having issues loading up the Elementor editor. It shows on the Chrome console:
Mixed Content: The page at 'https://website.com/wp-admin/post.php?post=2958&action=elementor' was loaded over HTTPS, but requested an insecure resource 'http://website.com/api-json/elementor/v1/global-widget/templates/'. This request has been blocked; the content must be served over HTTPS.