Tap not workings

Question

Hi I have created a windows phone app 7.1 that counts the taps, it has a reset button as well, I have coded it and no errors are showing, the app opens perfectly in the emulator but when you tap the screen no count happens, I have been through the code so many time Im nearly dizzy .
 
anyone who can spot anything wrong would very much appreciated.
 
Source code attached.
 
Any help really appreciated.

Mark