The slider in the pop-up window works after resizing. What could be the problem?

Question

Slick

The problem is the following: There is a pop-up, when you click on the picture, the pop-up opens, there is a slider, but the slider works only after resizing. What could be the problem?

$(".slider").slick({});

        var num = 1;
        $(".image").click(function(){
            var src = $(this).attr('src'),
                thumb = $(this).attr('data-thumb'),
                num = $(this).attr('data-num');
            $(`#${thumb}`).css('background-image', `url(${src})`);
            $( '.slider' ).slick('slickGoTo', parseInt(num))

            
        });
        $(".blog-thumb").click(function(){
            var thumbSlider = $(this).attr('data-slider');
            $(`#${thumbSlider}`).fadeIn();
        });
        $(".to-main-button").click(function(){
            $('.popup-slider').fadeOut();
            
        });

Here is the site site
Pictures in the block LATEST BLOGS
Only the first one works.
I would be grateful if someone could tell me what the problem is