From your screen grab, I see you have two Master Pages (labeled Page1 and Page2) and at least two pages (one labeled HeaderPage1 and another labeled Page1Item).
Without seeing more of the hierarchy and not knowing whether you have any flowed content, this is the best guess I can give you:
The blank page you're experiencing is a result of not properly setting how many times to replicate/repeat each Master Page.
For instance, if you have Master Page Page1 set to repeat and your content (presumably flowed) goes beyond page1, it will print onto another Master Page Page1. Then Master Page Page2 prints off all blank because all the content printed on Master Page Page1.