Trai — unsolicited telemarketing

Malls like big bazaar, more ask for customer mobile number (Compulsory) for billing, which is arrogantly and shamelessly sold to telemarketers without the customer's knowledge and consent. Later, the customer is harassed by untimely telemarketing calls for credit cards, personal loans, even if he is registered with dnd.
Your so called dnd app is nothing, but a fancy one, which doesnt serve the purpose. For e. G. A rogue bank like axis, sends sms from different headers for loans. Even if you complain about one header, the nonsense repeats sometimes, from the same header. Do you expect the consumer to complain about every number/ header these rogue banks use to send sms or call?
It is an illegal huge network. A rogue marketing agency buys the data from the malls, which is further availed by other rogues like hdfc bank, etc.
When contacted these rogues (Hdfc, axis, indusind) pretend innocence and intimate that the telemarketing number doesnt belong to them.
In the end, the customer is the sufferer, even though he is registered with dnd.
If such nonsense, is encouraged by trai, ignore this complaint, else take strict action.