How do I make it print only one print? (Isogram)

Question

I have a problem, when It loops though the code, it prints both the text in the if-statement and in the else-statement.

inp = input("Write a word to se if its a isogram: ")
word = inp.lower()
multi = []

for char in word:
  if char in multi:
      print("not")
  else:
      multi.append(char)
      print("It is")