How to update accruals after condition change in the condition contract?

Hello,

I have a question regarding the transaction WB2R_UAC to update the accruals.

I have posted a delta accrual for a condition contract, in the settlement document the rebate rate is 2%.

Later on I changed the condition rate in the condition contract from 2% to 4%

Then I wanted to update the posted accruals by WB2R_UAC, but the it shows that no condition contract has been selected for settlement.

I have checked the customizing that the condition change is relevant to the accrual update, the condition contract is active, and there is a free settlement date in the settlement calendar for the accrual update.

Does anybody have any idea why the accrual update is not working? How does WB2R_UAC suppose to work?

Thank you.

Zhang