Hi Sumit,
Please follow the below steps
1) Cancel Credit memo.
2) Delete Credit memo Request .
3) Then go to T.Code : VBO2 ,Enter Rebate agreement number and
under SETTLEMENT---
Change Minimum Status = NOT RELEASED.
By this way you can open the rebate agreement.
Could you Please explain the business scenario,for which the rebate agreement to be opened,once it has been settled and cleared.
please reward points ,if it is helpful.
Regards
Jeeva