Menu Builder - top level items and sub items

I have created a Top Level item and placed a sub item beneath it in the Menu Builder area - I was hoping (perhaps naively) that the sub menu item would link automatically to its Top Level parent - but it does not - - when I hover over the top level item I do not get a drop down menu like the others.

I know I am not soing something roight but just not sure where to begin - can someone please point me in the right direction?

thanks

Jeff

can you perhaps send a screenshot of the back-end work, as well as the result on the front-end?