Max and Rank not returning expected results

I have what I thought was a simple solution to return the earliest date in each group for a large number of records.

WITH FEES
AS
(
SELECT
    IT_NO               AS ITEM_NO,
    MAX(FEE_TRAN_DT)    AS FIRST_FEE_ASSESSED_DATE,
    RUN_DATE,
    RNK
FROM
(
    SELECT
        IT_NO,
        FEE_TRAN_TY,
        FEE_TRAN_AM,
        FEE_TRAN_DT,
        RUN_DATE,

    RANK() OVER
        (PARTITION BY 
            IT_NO,
            FEE_TRAN_DT,
            RUN_DATE
        ORDER BY 
            IT_NO,
            FEE_TRAN_DT,
            RUN_DATE)
    AS RNK
    FROM DM_MORTGAGE.FEE 
    WHERE 
        FEE_TRAN_DT > '01-MAY-20' AND
        FEE_TRAN_TY = 'A' --AND 
)
GROUP BY IT_NO, FEE_TRAN_DT,  RUN_DATE ,RNK
ORDER BY IT_NO, FEE_TRAN_DT,  RUN_DATE, RNK
)
SELECT * FROM FEES;

I wanted to see is this:

What I actually got was this:

I've struggle with this for way too long, and am unable to figure out what is going wrong. Any help would be most welcome. Thanks

Don't include the dates in the PARTITION. Just PARTITION BY it_no and then ORDER BY the dates (and you don't need to use MAX - which would be wrong as you want the earliest not the latest, instead, filter on the rank):

WITH FEES AS (
  SELECT IT_NO,
         FEE_TRAN_TY,
         FEE_TRAN_AM,
         FEE_TRAN_DT,
         RUN_DATE,
         RANK() OVER (
           PARTITION BY IT_NO
           ORDER BY FEE_TRAN_DT, RUN_DATE
         ) AS rnk
  FROM   DM_MORTGAGE.FEE 
  WHERE  FEE_TRAN_DT > DATE '2020-05-01'
  AND    FEE_TRAN_TY = 'A'
)
SELECT *
FROM   FEES
WHERE  rnk = 1;