I am new to wordpress and hosting, so I just thought I could move my WordPress site (files) from the subdomain to the main domain and everything will work. It worked actually except for the URL in the main domain changed to show the URL for the subdomain. (Later I found out I could change the URL's in the settings.
So I followed this tutorial ( http://www.wpbeginner.com/plugins/how-to-update-urls-when-moving-your-wordpress-site/ )to fix the problem and used the plugin "Velvet blue Update URL" to update the URL's but then everything got messed. And the site both in the main domain and test domain does not show appropriate links. And the slides keeps loading.
Also in the main domain I cant access my theme options (using Avada theme).
I deactivated all plugins to check if a plugin was causing these errors, I saw some changes when uninstalling the polylang plugin. But I have to keep it because I have my site in two different languages. (Actually when deactivating the polylang plugin my subdomain shows the site with almost no errors)
What can I do to save myself from all this mess?