If you're hearing a honking sound coming from your car, it's likely that there's an issue with the horn. The most common reason for a car horn to stop working is a blown fuse. You can check your vehicle's fuse box to see if the fuse for the horn has blown. If it has, simply replace it with a new one and see if that solves the problem.
Another possibility is that the horn itself is damaged or corroded and needs to be replaced. This is usually more expensive than just replacing a fuse, but it may be necessary if the damage is severe enough. If you're not sure what's causing your car's horn to honk, it's always best to consult with a professional mechanic to diagnose and fix the problem.