Payment Entry: Supplier required against Payable account

I will try to post a simple payment entry for the Employee with a stamp duty deduction using the Payment Entry Form Pay Option. this stamp duty deduction is posted by the Payment Deductions or Loss section.

After saving the transition appeared the submit button but it will submit and give the following message given below

what is the cause of that issue (Payment Entry: Supplier required against Payable account) and how is it overcome?
thanks
Dilum

you have to mention supplier in payable to section.