If you have accidentally added (or perhaps carried forward from a previous version) any dependants, you'll have to remove them before selecting no and continuing. Instead of saying no, I don't have dependants, say yes. You'll see in any dependants in the table that appears.

From here, click Remove next to each dependant until they are all gone, then choose the no radio option and hit continue. 

If that doesn't work try adding a dependant and then removing again, to see if that resets things for you.

If that still doesn't work there may be some corruption in the return, and the easiest way to fix it would probably be to create a new return in the return manager (To do so, click Tools > Return manager and choose create a new return).