National Highways Authority Of India [NHAI] — charged extra on delhi - manaser toll plaza

Address:

Gurgaon, Haryana, 122009

Today on 22nd may 2018 while heading towards jaipur, i have been charged extra at manesar gurgaon toll plaza... When i was crossing at 8:55 am, as at toll they asked me to pay in cash saying fast tag is not working... But once i crossed toll i got a message saying i have been charged at toll... So basically paid rs. 65 as cash and 65 through fas tag... Also what i have noticed i have waited for 25min at toll plaza in fas tag line but other lane was working for free... So whats the benefit of having fas tag...