Updating to WP 5.6

I have updated the core to WP 5.6 – When adding a ‘new post’ I am unable to see the categories and when looking in the console have the following error. It appears that the resources are not loaded over HTTPS.

Mixed content: load all resources via HTTPS to improve the security of your site
Even though the initial HTML page is loaded over a secure HTTPS connection, some resources like images, stylesheets or scripts are being accessed over an insecure HTTP connection. Usage of insecure resources is restricted to strengthen the security of your entire site.

To resolve this issue load all resources over a secure HTTPS connection.

4 resources
Name	Restriction Status
?per_page=100&context=edit&_locale=user	blocked
?_locale=user	blocked
?per_page=100&orderby=name&order=asc&_fields=id%2Cname%2Cparent&_locale=user	blocked
?context=edit&_locale=user	blocked

I am hoping that someone here can advise?

Appreciate the help