Passport Office Hyderabad — Staff behaviour

Respected sir/madam,
I recently visited the passport office at Ameerpet, Hyderabad. We were very hurt with the staff at counter C. They were talking in Malyalam, thinking that we do not understand. They said "these people don't know anything and come and wast our time". I understand that the general public may not know many things about the passport office procedures and I can understand the staff may be under so many pressures, but insulting the customers is not ethical and is very rude. Apart from that, they helped in clearing out doubts. Please don't consider this as a complaint but a reminder of being courteous.
Thank you.