TDS amount at the time of Invoice posting

Hi Experts,

Scenario is, Total Vendor payment is 70000

Down payment of 20000 with TDS 200@1% is done

now at the time of Invoice posting through f-43, how should system automatically Picked the rest of the TDS amount (500) without manually entering the 50000 amount in Base value (WITH HOLDING TAX TAB)

Rgds,