supplier bank account attached to document payable is end dated

hi experts

Please help me as i am struggling with the issue mentioned below :

I have created a receipt in AR. Applied it to Refund in the "Apply to" field.  From the refund status taken the invoice number and queried in the AP.  Here in the invoice workbench Remit to Bank ; Remit to Bank Account Number; are not populated and they are greyed out. I tried to change this. I have enabled in the Payable Options " Allow Remit to Supplier Override".  Now i am able to select the Customer Bank Account to whom the refund is going to be made. But when i am trying to make payment through "Pay in Full"