Promotion Slider Help! Please! 2 images shown at once.

I am desperate! I’ve tried several plugins and this might be my last shot.

I am creating a website for my parents and I want a image slider to give it that professional look.

I followed the instructions:
-Create a category
-Add Promotions
-Fixed a couple of the slider options
-Then I placed the code in my home and driving page to see what it looks like:
[promoslider category="home"]

Problem: the two images are shown at once. Can anybody help me?