Dog keeps setting the alarm off please help.

Hello.
Wonder if anyone can help. Recently purchased a 2018 Megane. Every time I Stop for petrol etc If the dog is in the car after a minute or so the alarm will go off. I can’t even leave it unlocked as I have one of the cards (key) Which automatically locks it when I go to pay for petrol.
I can’t find anything in the log book to show me how to disable it or what to do. I’m hoping there is a simple way.
Thank you