Alarm sounds when I open passenger side door. No key fob to turn off?

What is your question?

I just bought this car. I was given 2 sets of keys and a key fob for the door locks. The other day I used my key in the passenger side door and the horn started honking. It continued until I opened the drivers side door and put my key in the ignition. Where can I get a new alarm key fob?

What makes this problem better or worse?

Na

How long has your 1998 Plymouth Voyager had this problem?

1 week