Section Headerview with button

I have a tableviewcontroller, and in one of the section headers, I have a button. When the button is tapped, I insert additional elements into the section. If the button is tapped again, the elements are removed. This has the effect of a collapse/expand tree. The button and logic work fine for the most part.

The tableViewController is part of a navigation. If I navigate backward, then come back to this tableViewController, the button tap works, the code-behind is fired in debug mode, the code to insert and remove section elements fires, but the view never displays the extra elements.

Any ideas?