Hi there,
by inspecting the Slick Slider i can see the Javascript which looks like this:
<script>;jQuery(document).ready(function($){$('.slick-slider-5550').slick({dots:false,infinite:true,speed:1000,arrows:false,autoplay:true,autoplaySpeed:5000,fade:false,slidesToShow:1,slidesToScroll:1,lazyLoad:'ondemand',mobileFirst:true});});</script>
The issue is this argument: arrows:false
This is removing the default navigation arrows.
Are you using a plugin to add the slider? Is this an option?