National Highways Authority Of India [NHAI] — fully charged in return journey with 24 hrs at toll plaza

I am holding fast tag (Account no:[protected] from bank of baroda. I have passed manoharabad (Toopran) toll palaza on 3rd november and they deducted my fasttag. They deducted rs. 80 amount. I have crossed again the toll plaza within 24 hours of time again they deducted rs 80. Ideally i should get charged for rs 40, but they charged full amount.
They are cheating the customer who use fast tag. Please take necessary action against them. It should do automatically but it is not happening.