sap error Nr 0249 (The deferral date must be after due date 29.12.2015)

Hi Experts,

I want to create 2 installments plans for a business partner having 2 contracts.

For the first installment plan I use open items from the first contract and it went successful.

But by creating the second installment plan using open items from the second contract, I get the sap error

Nr 0249 (The deferral date must be after due date 29.12.2015)

1. 29.12.2015 is the due date of the last term of the first installment plan.

Can anyone suggest an idea, I will be appreciated.

Regards,