This happened to me 2 years ago. The fire alarm was going off pretty much every day.
It was usually just due to people being careless. Almost always cooking something that produced a lot of smoke without switching the extractor fan on. Or even showering with the door open. They can even be set off by people spraying deodorant in their rooms! It's a huge pain in the arse, but it happens at university halls. The fire alarms are way too sensitive.