National Highways Authority Of India [NHAI] — No Return Concession at Sivaya Toll Plaza

At Siwaya Toll Plaza if you are cpming return on the same day i.e. within 24 hrs, no concession is available. If you are paying Rs 85 in coming, you will have to pay same amount even if you are coming back within 24 hrs. Why this is happening at particular toll whereas at other toll plaza you will pay half amount if returning within 24 hrs