TNSTC — Charges for using laptops

Address:

2/155,East st,Therkur,Sattur

Dear TNSTC Management,
I am travelled Thirumangalam to sattur in thirunelveli bus.My co-passenger is using his laptop and conductor is noticed if you carrying using laptop also chargeable. He showed me a rule book mentioning luggage charges for computer, monitor, keyboard n other accessories. I explained him clearly that the computer meant a desktop n not a laptop. He refused to accept without any reasons.I need clarification about I am wrong or the conductor is correct.