Extra buttons on page when preview.

I found a weird issue on SKUID form when using wizard. 

I am using wizard with multiple steps. Having two buttons on each steps for next and previous. When I try to add one more button and save the form. In preview, it shows two more buttons, i.e. total five buttons. Now sure how these two extra buttons coming up. 

The weird thing is, I am not able to see these two extra button in SKUID page editor.  

Finally, need to remove the extra buttons through XML view.