tub/shower single handle problems with diverter

[poochokid]

My shower is less then 2 years old. When we want to use shower some times we pull up diverter lever amd the water only comes out the tub spout and some time it works fine and spays out the shower head. What is going on with it and how can I fix it?

[HayZee518]

diverter

unscrew the spout and see if the flap seals off the nozzle part when you pull up on it.
worse case go to a big box store and get another one.