When I receive a call on key 0 I get caller ID no problem. While using key 0 if I receive a second call no caller ID is displayed from the incoming call. When the second call comes in I just get a tone and key 1 flashes. If I answer the second call the caller ID of the second call comes up as the key lamp goes steady. Is this a shortcoming because of the small display or am I missing an option? I have the cls set to add cnda dnda. When I receive a call on key 0 I get caller ID.