Both of the plugin uses the same menu position, Thats what making the problem. As it mentioned on http://codex.wordpress.org/Function_Reference/add_menu_page#Parameters
The position in the menu order this menu should appear. By default, if this parameter is omitted, the menu will appear at the bottom of the menu structure. The higher the number, the lower its position in the menu. WARNING: if 2 menu items use the same position attribute, one of the items may be overwritten so that only one item displays!
Default: bottom of menu structure
So now we now made our plugin to get automatic menu position. It will be at last of the menus. Disable and remove the plugin and reinstall the Floating Social Media Icon and it will fix the issue.
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