If you're noticing that your belt is snapping more frequently, it's likely due to one of two reasons. Either the belt is old and needs to be replaced, or the pulleys it runs over are misaligned.
Belt deterioration is a common issue, especially if you live in an area with extreme temperatures. Over time, the heat and cold can cause the material to break down, making it more susceptible to snapping.
If you think your belt might be getting close to the end of its lifespan, it's a good idea to get it checked out by a mechanic. They can give you a better idea of how much life it has left and whether or not replacement is necessary.
Pulley misalignment is another potential cause of a snapping belt. If the pulleys aren't lined up correctly, they can put undue stress on the belt which can lead to breakage. This is usually easy for a mechanic to fix - they'll just need to readjust the position of the pulleys.