Scratch

I'm trying to make a pong program but the ball won't regester that it has touched the left edge which I have colored blue.  My code for it currently is

[when flag clicked]
set player 1 to (0)
set player 2 to (0)
forever
move (3) steps
if on edge, bounce
if <touching sprite1>
play sound Laser2
turn 180 degrees
point in direction (pick random (70) to (180))
if <touching sprite2>
play sound Laser2
turn 180 degrees
point in direction (pick random (-70) to (-180))

[when flag clicked]
go to x:-170 y:-20
forever
if <touching color red>
change player 1 by (1)
go to x:-170 y:-20

[when flag clicked]
forever
if <touching color blue>
change player 2 by (1)
go to x:170 y: -20

Is my problem the fact that the right edge isn't touching blue?