A Class alarm goes off intermittently

[A.J.]

My Daughter has a 2019 A Class A180d. Over the last 3 days the alarm has gone off intermittently. Each time she has gone out made sure all the windows are shut re-closed all of the doors including the tailgate and reset the alarm. it has been about once a day with the exception of today when it has gone off twice. Any clues as to why this is happening will be gratefully received

 

[AMGeed]

Possibly the internal battery has corroded inside the alarm module?
It seems quite a new car for this to have occurred though.

 

[Blobcat]

Could also be a flying insect. Turn the interior motion sensor off (what most car drivers struggle desperately with on ferries…) and lock the car.