ninja forms not working

Hi I am using the theme evolve and it was all going well until I tried to add a ninja form to the website I went and downloaded ninja forms I then went into ninja forms and built the form I wanted I then used the piece of code they gave me to put onto my website but it just comes up with a lot of lines and no writing it looks nothing like the form I created I have a ninja forms on another website and it comes out exactly how I created it but for some reason it’s not working with this theme does anybody have any suggestions I would really appreciate it

https://ww.wp.xz.cn/plugins/ninja-signature-contract-forms-add-on/