List of Worlds not Loading - cannot get to older worlds

My son has 1332 worlds on his Android tablet.  When he tries to scroll past the most recent 20 worlds, the display begins to get smaller and the list appears smaller on the screen.  As he continues to scroll down, the number of worlds in the list shrinks from 8 to 7 to 6 etc., until no worlds appear in the list.  You can continue to scroll but no worlds appear.  It's as if the display is shrinking the farther you scroll down in the list.

This is keeping him from getting to worlds that he created when he first started playing the game.