This message is for Luis, who is currently helping me to restore my site.
Please let him know that there is a plugin on my site, something like a calculator field form that has not been updated. According to the developer, it cannot be updated or my custom-made calculator form will not work. So do leave it as it is for this plugin.
And it cannot be the plugin that was giving this conflict problem because the site and log in was working fine after it was installed.