Probably a dumb question but I can't figure it out. Just bought a new Browning Citori 16 gauge - fresh out of the box. The gun will only fire one barrel at a time. After firing the bottom barrel - it won't shoot the top barrel unless I move the safety back to safe and then to fire. I can move the barrel selector so that the top barrel fires first and same thing - top barrel will shoot but nothing happens if I pull the trigger a 2nd time. If I move the safety back to "safe" and then to fire and pull the trigger again - the gun shoots the 2nd barrel. What's the problem?