Nissan Micra on going boot problems & battery drainage

In the beginning as I was driving along the boot started popping open and the alarm would go off so I had a new micro switch put in but the auto electrician did comment at the time how the old switch seemed water damaged as there's no sealant around the top of the boot switch housing allowing water and damp to get in. Well everything seemed fine for a short period and then once again the boot started opening again whilst driving along but also when I pressed other buttons or switches like the window demister or my wipers and then if I didn't use my car for 24 hours the battery would drain so I called the auto electrician back out again who once again said the switch was still managing to get damp inside it so this time he replaced it with a waterproof switch and also used lots of sealent in and around the switch and along the top of the housing and once again it seemed fine for a short while but now the boots back to popping open again! I haven't left the car for over 24 hours yet but I'm sure if I did the battery would be dead again. I seem to be chucking money at this problem but getting no permanent fix and its gutting as I don't have an endless amount of cash. The electrician has checked the wiring in the car for breakages but hasn't found any so I don't know what to do next? Any advice would be greatfully received. Thanks in advance. Leanne.