Horn buttons sometime develop an intermittent bad ground through steering column parts. Try turning steering wheel hard right and hard left while pushing the horn button or ring to see if they'll beep.
Find your horn relay.Take a jumper wire and touch the power terminal and the horn terminal . If the horn honks try touching the horn button terminal ( the one you havent touched yet)to ground. If the horn does not sound on the first test check for power on the bat terminal, if you have power the horn is the problem. If it does sound but does not on the second test the relay is bad.
if it sounds on the second test the horn button or the wire to it is the problem.