I am trying to call support to see if we successfully changed our transmitter code. The recording at Wayne Dalton gives a website www.gdosupport.com but no phone number. Our transmitter was stolen and we want to be SURE our code has been changed. We followed the instructions and everything worked as stated, however my car with Homelink was still able to open the door even after we thought we completed changing the code. Is there a way to determine whether the code has really changed??