I followed the steps, and the programme is able to execute without error, but no response from the servo. The external power for the PCA9685 is a 9V battery. I've checked the motor, and it's healthy.
Any idea why the servo is not responding?
Hmmm, I'm not sure what the problem is, but the battery I used was a 5V not a 9V, maybe that's the problem?, also I recommend you to check the wiring, and try with the second library.