How do you fix the horn on the steering wheel?

Chances are it is a fuse or the horn control relay but to be sure here is a wiring diagram for the horn so you can see how it works and where to check for power loss. I have also included a guide to show you how to check for power.

https://www.2carpros.com/articles/how-to-use-a-test-light-circuit-tester

In the under-hood fuse panel check the 30-amp horn fuse. If that's okay swap out the horn control relay which is in the same fuse panel. Check out the images (below). Please let us know what you find.