You did not tell which board you use: Own pcb? Cypress kit?? Which one ???
Depending on the board there are already I2C pullups mounted.
Your device is set (in system resources) to 5V, your LCD is powered with 3.3V, does that match? How is your PSoC powered?
You may reduce (as a test) the I2C speed to 50kHz.
Juanes: Spec for the NewHaven display says 5.0 volts and your design says 3.3v I would fix that issue. Also the Spec says that it takes 1ms for writes so you may need to change your delays. If you are using a pioneer board it already has pullup resistors. So with yours you are reducing the pullup value due to the resistors in parallel .
Thank You Bob and Bob Goar, Im new to I2C thanks for your help!!