Hi,
i am having problems with my alarm, when i got out this morning at work , as usual i pressed the key fob and the central locking locked as normal ,but then it unlocked itself again and wouldn,t stay locked , when i tried with the key it only locked the drivers door , normally it would lock the lot , only way i can secure it is push the buttons down on thedoors with thedrivers door open and then lock that door with the key. when i open the door the alarm will go off but but will not reset . could it be the battery low in the landy or in the fobs ? or more sinister

one of the door pin switches not working properly so the car thinks one of the doors is open??? wild guess but have had this on other cars

i went round and opened and shut all the doors as that went through my mind too ,will need to look in the light, dark at 5:30 am in the car park and late for work also dark and freezing at home at 6 at night

Maybe that the contacts in the drivers door master CL actuator have gone lazy
There is some adjustment in the actuator mountings, only a few mill but that will allow the operating rod to move deeper into the actuator and therefore operate the contacts.
You will have to take the door card off to do your fault finding so worth a try.