Email field does not appear on iphone

Hi there,
I’ve this awesome plugin in the page-title widget on my eleven40 theme.

The email field was very long before and used to occupy the whole width of the page. Now I edited its width to look smaller and nicer.

But when you check it with an iphone (and I guess with any mobile) the email field disappears and you can only see the red button.

https://letstalksex.net

Could anyone please help me fix this?

Thank you!
Deon

https://www.ads-software.com/extend/plugins/genesis-enews-extended/