Hold the release button down and tap the nose on a hard surface if the rivet pinhole gets stuck inside the tool.
Shove down on both handles and press the release button if the rivet gun will not move in reverse. If this will not reverse the tool, unscrew the nose tube and use a wire brush to remove any dirt or debris caught in the mechanism.
Remove the nose tube and tighten the jaw holder if the fastener will not pull a rivet. Tighten the jaw holder by turning it to the left.
Order a replacement nose piece if the rivets will not fit into the riveter.