Good afternoon Ken Johnson,
I had a similar problem after a total discharge of the battery. A new battery and new alarm didn’t work, had to resort a couple of times to removing the fuse. McGraths although very helpful couldn’t get to grips with the problem, they suggested Jardine motors, Colchester, who now only deal with Ferraris but have retained the Maserati diagnostic kit. (If you are in the South East area?) I found them very helpful. Their procedure didn’t totally cure the problem, which sounds much simpler than yours, I just have to remind my self to disarm the locking mechanism via unlock on key fob before I open the door to get out. sometimes I forget, oh oh damn.
I hope that helps, Dave Jenkinson