If you have the fob present and it is the button less one, is the battery in it OK. Can you arm and disarm the alarm by walking away and coming back and do the lights flash and siren chirp if you have one so you know it's working?
If all the above is YES, then the procedure should work on it if done properly. No magic buttons here, just the procedure and the working FOB. Hope there are no cell phones on your belt or close by that may be interfering with the signal. Also try passing the FOB around the area of the side cover on the right (intake side) where the antenna is located to see if it will deactivate the alarm.
If all this fails, It looks like a trip to the dealer is in store if all the above fails.