Slider Help

We recently had a website built by a vendor and I am now trying to update certain aspects of it. For the most part I am doing great but I am stuck on the Sliders. I was able to add 2 more sliders but the sliders will only show 3 at a time when I have 5 published. Is this something I can change in the code? If so, where do I find said code? And the developer is not responding to emails or skype.