Why isn't my JotForm coming up on my website?

I'm using Tumblr and I embedded my form into my contact page. Initially my form worked but I checked a few weeks later and the form will not show up on my page even after I recopied and pasted the code.

There is a CSS code on your web page which is hiding all the iFrames including the form frame.

iframe {display:none !important;}

Please check this out.