Checkbox Trigger not working?

Looks like the whole part of this code isn’t working. What could be the reason? Any help is really appreciated. Thanks.

if(gwfcBodyCheckboxTrigger.is(':checked')){

		$('#customize-control-gwfc_body_sub_title').css('display', 'block');
		$('#customize-control-gwfc_body_font_family').css('display', 'block');
		$('#customize-control-gwfc_body_font_weight').css('display', 'block');
		$('#customize-control-gwfc_body_font_color').css('display', 'block');

	}

https://www.ads-software.com/plugins/google-web-fonts-customizer-gwfc/