Website form (sometimes) not working

Hello,

I currently run a website where people can submit their own content through a form. I just started it and earlier today, everything was working great and people were able to submit their content. However, now all of a sudden, it doesn’t work anymore. The plugin for the forms is Gravity Forms and when you click “Submit” now, it just redirects to the same form, empty, and the content is not submitted.

It’s really weird because I didn’t change anything in the code or anything. Could it be my host? Have any of you had a similar experience?

Thanks!

PS: My website is http://www.minecraftinventions.com and the form is http://www.minecraftinventions.com/submit/submit-a-map