Those three channels are the 3 free preview channels you get when the unit is not activated.
First, verify to make sure you have the correct radio ID number. If the number is corrtect, take your vehicle outside where it has a clear view of the sky and let it sit, with the radio powered on, for about 15 mins.
if that does not work you need to have Xm re-send the activation signal. When you first activate your XM they request that you have your car outside and powered on for 15-20 mins until the unit is activated. if you did not do this the first time make sure you do it the 2nd time.
i dont know if you can re-send the signal yourself online or not. you may have to call XM to have them do this.