Servo not working

hi guys i have a query please try helping me out i have brought 5 servos from hobbyking in which one of them is not working

it got stuck it is not moving its shaft i think so it is jammed now what should i do

If the shaft is twitching

If the shaft is twitching like it’s stuck. You can always try putting a 470uF capacitor across it’s power leads. + end of the cap to the + end of the servo and - end to -.

straight from a Hitec servo manual

Servo is locked in place:

Open the case and make sure the gears are properly aligned.
Next check the case top for wear. If wear is evident, replace the case.

Maybe it is defective.