Correct format for date range prompt

[Shailaja0520]

Hi,
i have a parent report with 2 date prompts.
and data item= concatenating 2 dates-'Between '||?Parameter1?||' and '||?Parameter2?

i have a child report with a date range prompt-parameter 3 and passing the data item from parent to this report.

i am able to display this data item from parent to child report.

but when i m using this for filtering the data in child report--i.e in_range ?parameter3?
it is throwing an error of incorrect format.

i am not supposed to change  anything in child report.