I had success getting it to translate the message after having it first list all the letter pairs and then giving it very detailed step-by-step instructions with a sample word (chicken). Here's the final ChatGPT response from our conversation.

I first tried it with just one word (pebff) but it forgot the final s. But it did great with the whole sentence!

---ME---

Yes, please decode the following message: "Jul qvq gur puvpxra pebff gur ebnq?"

---CHATGPT---

  To decode the message "Jul qvq gur puvpxra pebff gur ebnq?", we can follow the steps you outlined earlier:

  First, separate each letter on its own line:
  J
  u
  l

  q
  v
  q

  g
  u
  r

  p
  u
  v
  p
  x
  r
  a

  p
  e
  b
  f
  f

  g
  u
  r

  e
  b
  n
  q

  Then find the ROT13 equivalent of each letter:
  J -> W
  u -> h
  l -> y

  q -> d
  v -> i
  q -> d

  g -> t
  u -> h
  r -> e

  p -> c
  u -> h
  v -> i
  p -> c
  x -> k
  r -> e
  a -> n

  p -> c
  e -> r
  b -> o
  f -> s
  f -> s

  g -> t
  u -> h
  r -> e

  e -> r
  b -> o
  n -> a
  q -> d

  Next, get just the second letter on each line:
  W
  h
  y

  d
  i
  d

  t
  h
  e

  c
  h
  i
  c
  k
  e
  n

  c
  r
  o
  s
  s

  t
  h
  e

  r
  o
  a
  d

  Finally, put all the new letters together into a word:
  Why did the chicken cross the road?

  So, the decoded message for "Jul qvq gur puvpxra pebff gur ebnq?" is "Why did the chicken cross the road?"