warning message after installing plugin

I installed Storefront Design Customizer and then started noticing a warning message. See below. i deactivated Storefront Design Customizer and the message went away. I have it currently deactivated.
Did I do something wrong that is affecting this plugin? novice here and just going through my first setup of woocommerce storefront.

Warning: call_user_func_array() expects parameter 1 to be a valid callback, function ‘sdc_social_menu’ not found or invalid function name in /home/feltwerker/feltwerker.com/wp-includes/class-wp-hook.php on line 286

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