Ways to be stuck on an island?

Okay I'm writing a story and two of my characters go to this small island for work, it isn't deserted but close. There are about 50 villagers there. Now I need a way for them to get stuck on the island, not like by shipwreck or anything, because they can leave the island in normal conditions. But, I need a way for them to be stuck on this island for about 2 months. Any ideas?