Support

According to Google Search Console your site is providing its own canonical URL. There are two possibilities here. You have either set up a custom domain name in the System - SEF plugin (in this case and this case only a canonical URL is, indeed, defined by Joomla) OR you are using a third party extension which defines the canonical URL of the page. Please note that Admin Tools does not define canonical URLs nor can it affect them. Therefore this issue is out of scope of our support.

That said, I will try to give you some pointers based on my experience. Don't expect me to follow up on these suggestions; these are merely the things that I would be looking at my site if it had the same issue :)

Check your configuration.php file. There's the $live_site parameter there. If it's empty, no problem, leave it like that. If it has a URL make sure it begins with https://, not http:// (that's the most common mistake I see in sites switching to HTTPS)/

Now, let's check if you have entered a custom URL in the System - SEF plugin. If that URL has http:// in front change it to https://. If it's empty, leave it like that. You are only supposed to enter a URL there if your site is accessible from different domain names and you have not set up redirections from the secondary domains to the main one.

Go to Global Configuration and set Force HTTPS to Entire Site. Otherwise your site can be accessed under both HTTP and HTTPS which might be an issue with third party sitemap and SEF / SEO extensions.

Are you using a sitemap extension? Ask its developer if you need to reconfigure it or regenerate the sitemap after switching your site to HTTPS.

Are you using a SEF or SEO extension? Ask its developer if you need to reconfigure it or regenerate the sitemap after switching your site to HTTPS.

I hope this helps!

It should, but it might take a while. Based on my experience it takes anywhere from a day to two months depending on how often they crawl your site. Our business site gets crawled multiple times a day -- every change is reflected on Google Search Console very fast. My personal blog takes 2-3 weeks.