After Goku fought Frieza and the planet blew up, everybody on earth thought Goku was dead. So they used the dragon balls to wish to bring Goku back to life, but the dragon then told them that Goku was still alive. They then asked the dragon to teleport Goku back to Earth. The dragon then said no, because Goku did not want to.
So why would the dragon listen to Goku, who was not making the wish?