I have JS Error when Scrolling Website. Here is Code:

$(window).scroll(() => {
    topOfFooter = $('.footer-sgm-main').position().top;
    scrollDistanceFromTopOfDoc = $(document).scrollTop() + 1350;
    scrollDistanceFromTopOfFooter = scrollDistanceFromTopOfDoc - topOfFooter;
    if (scrollDistanceFromTopOfDoc > topOfFooter) {
        $('.edc_course_show_fixed').css('opacity', 0);
    } else {
        $('.edc_course_show_fixed').css('opacity', 1);
    }
});

Error: Uncaught TypeError: Cannot read properties of undefined (reading 'top')