Calculate the sum of values for the columns that meet the criteria

I have sample data like below in my PieCloudDB Database:

I want to sum the Flow values based on the condition that Flag is 1, and the sum range is divided by Date(Merge consecutive dates), example output:

I tried this:

WITH CTE AS (
    SELECT
        date,
        flow,
        flag,
        ROW_NUMBER() OVER (ORDER BY date) - ROW_NUMBER() OVER (PARTITION BY flag ORDER BY date) AS grp
    FROM mytable
    WHERE flag = 1
)
SELECT
    MIN(date) AS start,
    MAX(date) AS end,
    SUM(flow)
FROM CTE 
GROUP BY grp
ORDER BY start;

But I don't know why I get the output like this:

Try it like here:

WITH    --  S a m p l e    D a t a :
  tbl_data ( a_date, flow, flag ) as 
    ( Select To_Date('2024-05-20', 'yyyy-mm-dd'), 583, 1 From Dual Union All
      Select To_Date('2024-05-21', 'yyyy-mm-dd'), 947, 0 From Dual Union All
      Select To_Date('2024-05-22', 'yyyy-mm-dd'), 216, 1 From Dual Union All
      Select To_Date('2024-05-23', 'yyyy-mm-dd'), 375, 1 From Dual Union All
      Select To_Date('2024-05-24', 'yyyy-mm-dd'), 492, 1 From Dual Union All
      Select To_Date('2024-05-25', 'yyyy-mm-dd'), 816, 0 From Dual Union All
      Select To_Date('2024-05-26', 'yyyy-mm-dd'), 753, 0 From Dual Union All
      Select To_Date('2024-05-27', 'yyyy-mm-dd'), 629, 1 From Dual Union All
      Select To_Date('2024-05-28', 'yyyy-mm-dd'), 104, 1 From Dual Union All
      Select To_Date('2024-05-29', 'yyyy-mm-dd'), 567, 0 From Dual Union All
      Select To_Date('2024-05-30', 'yyyy-mm-dd'), 128, 1 From Dual 
    )

... create a grouping id (grp) for rows with flag = 1 using Count() Over() analytic function conditionaly as in the inner query below - then do the aggregations where flag = 1 grouped by grp column in the outer query ...

--    S Q L : 
SELECT     Min(a_date) as start_date, Max(a_date) as end_date, Sum(flow) as sum
FROM     ( Select     a_date, flow, flag, 
                      Count(Case When flag = 0 Then 1 End) Over(Order By a_date) as grp
           From       tbl_data
        )
WHERE      flag = 1
GROUP BY   grp
ORDER BY   grp

/*    R e s u l t : 
START_DATE  END_DATE       SUM
----------  ---------  -------
20-MAY-24   20-MAY-24      583
22-MAY-24   24-MAY-24     1083
27-MAY-24   28-MAY-24      733
30-MAY-24   30-MAY-24      128      */

See the fiddle here.

NOTE:
The answer is tested with Oracle but uses standard SQL syntax. Sample data here is defined by a cte in WITH clause which you don't need. Just put your table name (or your cte name) instead of tbl_data in From clause of the SQL and make any other adjustment needed to fit your context (like column names ...).