MCD Parking — Charging extra for parking

Address: East Delhi, Delhi

At Nizammudin Railway Station 2 wheeler parking(sarai kale khan Side), I had to pay more than what it was written on the parking receipt.
In the parking receipt, it was written: " Rs 10 per entry for 10 hours and after 10 hours Rs 20". But for 26 hours the MCD authorized personnel charged me Rs 30 saying that "It is Rs 10 for every 10 hours". I refused to pay it then they were fighting with me and so at last I had to pay Rs30 as I was helpless there, against approx 4-5 persons.
I am hoping a strict action against them.
I also tried to complaint on :
http://111.93.49.28:18080/mcd_commonweb/GrievanceManagementtoLodge.action?RID=11...⇄

but here they have not implemented the complaint system for East Delhi area.