Conditional logic on a field from a previous page doesn't work

I have a multi page form, on page 1 there is a drop down box of options, and on page 2 I have a question which should only be shown if one of those options were selected. This isn’t working. I have tested and if they are on the same page it works ok. The form is using ajax, but turning that off doesn’t seem to help. Are conditional fields only supposed to work on the same page or can they cross pages? Just wondering if this is a bug or intentional. And is there a way to get around it? A hook perhaps to show or hide the field?

Thanks