HTTPS/SSL certificate doesn't work

I have set up my custom domain using the following 2 guides: and

But when I visit my website link from 1 of my browser, Brave in this case, it say that the connection is not secure. If I visit the same website with Firefox browser, the connection is secure and I see the lock icon next to my link.

Why is this happening ?

EDIT: Issue has been resolved with Brave with a browser restart. Maybe the website was in a sort of sandbox due to the fact that, before to force the HTTPS connection, I accepted in the advanced option to proceed anyway on the not secure website.