hi adriano,
I can’t see from the snippet you have shown whether you have set up your form correctly -
you need an opening and closing form tag, all input areas must be in correct input tags, and you also need a button type="submit" at bare minimum.
No form will work correctly on netlify without the basic building blocks.
This Common Issue is the first port of call to debug any forms issues.
If you are still having problems, please provide more information such as what you have already tried, and a link to your live form. 