Slick slider not working responsive?

Question

Slick

responsive doesn't work.
how to fix?

$('.slider_our_service').slick({
    prevArrow: $('#our_service ._nav-slider_prev'),
    nextArrow: $('#our_service ._nav-slider_next'),
    arrows: false,
    dots: false,
    infinite: true,
    speed: 300,
    slidesToShow: 3,
    slidesToScroll: 1,
    responsive: [
      {
        breakpoint: 1200,
        settings: {
          slidesToShow: 2,
          slidesToScroll: 1
        }
      },
      {
        breakpoint: 820,
        settings: {
          slidesToShow: 1,
          slidesToScroll: 1
        }
      }
    ]
  });

Answer 1

Need to add to page

<meta name="viewport" content="width=device-width, initial-scale=1"/>

Answer 2

Try including slick.js instead of slick.min.js