Have you updated the every instance of http with https? Because for the green padlock in the web browser, the every instance of http should get replaced with the https in your code, script, image path, configuration files, databases etc.
You can ask your web-developer to check this. You can check it in your Mozilla web browser just by right clicking on it and select the inspect option, debugger will get open and it will display the actual path of the http instances on your site.
OR
You can fire the query in database for checking the http instances.