Check in your underlying hardware schematic file to see whether the chosen pin is in use for something as I2C.
I strongly recommend to update Creator to latest version and to update the components of your project to latest.
Bob
Your clock for the PWM is too slow should be 12 Mhz. The Led pin doesn't need the external terminal checked in config. file for the pin. Here is your program with changes. I am running PSoC Creator 3.3 CP3 (3.3.0.9604) As Bob suggested please upgrade to the latest software.