Slider Shifted to Left

I recently looked at my website (messerstilp.com) today and noticed that the slider had shifted to the left on the home page. It was previously in the center which is where I needed it to be. I didn’t change any of the code as I am not too tech savvy, and I don’t know why it moved. Any suggestions as to how to re-center it?

https://wordpress.org/plugins/wp-nivo-slider/