Could BOTH my horns be bad?

To sum up others

Make CERTAIN you have a good ground, the bracket / mounting hole is usually best as the bolt as scraped it up a bit, but you can use screwdriver, scraper, whatever to do so. use a jumper cable , etc on the bracket to the battery post

Mark the adjuster so you know it's position (you can tune them) and don't be afraid to twist it back and forth. Often the threads of the adjuster are rusty, and THAT is what grounds the contacts inside. The contacts are often burned and twisting the adjust often causes it to conduct and you can then work the adjuster back and forth from there

Make sure you are using a good heavy wire, no14 is good. You can connect to the battery with say, vise grips and then touch the wire to the horn terminal by hand, but be careful you don't get burned. That contact can be warm, and the action of the horn can shock you.

If you get the horns working "on the battery" and they still won't operate, check the horns for voltage right at the horns. Access the horn wire (black) at the column connector. Stick a jumper wire in there and ground it to lock the relay energized. Then take a multimeter and leaving the horns connected, probe the horn connectors and look for "should be" nearly same as battery, AKA about 12V

To check for horn grounding with relay locked energized, touch your multimeter probe (other probe grounded) to the horn metal. If you read ANY voltage there, the horn is not grounded