Rebate Process

Hello,

I need guidance in rebate agreement processing,

I have created customer rebate agreement, and maintained sales goal in scale as from 100000 rebate should be 2%

i.e. system should accrue 2% rebate for sales volume 100000 for the specified period.

When I am settling the rebate agreement sales goal is not achieved for specified period of agreement but still system allowing me to settle the agreement.

credit memo is getting posted to accounting and amount is getting debited to customer.

pls correct me where i am going wrong..