"Convincer" is a word in ENGLISH

A man is flying in a hot air balloon and realizes he is lost. He reduces his altitude and spots a man down below. He lowers the balloon further and shouts: "Excuse me, can you tell me where I am?"The man below says: "Yes, you're in a hot air balloon, hovering 30 feet above this field.""You must work in Technical Support," says the balloonist."I do," replies the man. "How did you know?""Well" says the balloonist, "everything you have told me is technically correct, but completely useless."The man below says: "You must be in management.""I am," replies the balloonist, "but how did you know?""Well", says the man, "you don't know where you are, or where you're going, but you expect me to be able to help. You're still in the same position you were before we met, but now it's my fault."