Caesar's Cipher, step 11

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#1

Hi. I jut cant understand why my code output [“l”, “o”, “l”, “l”, “o”] insteat [“k”, “h”, “o”, “o”, “r”].

var alphabet: [Character] = ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j", "k", "l", "m", "n", "o", "p", "q", "r", "s", "t", "u", "v", "w", "x", "y", "z"]
var secretMessage = "hello"

var message = Array(secretMessage)

for i in 0 ..< message.count {

  for j in 0 ..< alphabet.count {

    if message[i] == message[j] {
      message[i] = message[j+3]
      break
    }
  }  
}  
print(message)