Metronome won’t stop

Help! When I tap the ticking metronome, it does not stop. If I tap the X, the icon disappears, but the ticking continues. No matter if I close the music, the ticking continues. It also seems to be adding beats if I try to change it, so the sound gets worse and worse. If I close and reopen the app, the ticking begins again. To survive, I’ve had to turn off the sound on my device. Any solutions??