Did you check trying code example PSoC4_CapSense_Tuner_I2C? (Navigate to PSoC Creator-> File->Code example)
Also, check if EzI2C and tuner I2C configuration settings are correct/matching (Send screen shots too)
Which USB-I2C bridge are you using? Please confirm if it is Kitprog present in the kit.
If you still face any issue, please attach your project.