Use Page Layout Tool > Edit System Margins. It looks as if one system has too large an upper margin or Distance Between set (unless you inserted a new page break unintentionally).

Is there a page break icon at the top of the 3rd page? The playback controls are in the way. If there is, delete it.

How do I delete it?  It won't let me highlight it.  Also, how did I put it there in the first place?  :-)  Thanks.

Ah.  I just found this old post about deleting page breaks.  For anyone else you needs it, here it is.  Also, if you don't have a mouse with a right click, press "control" click.