Bajaj Finance — complaint for unwanted sales calls

I am getting endless sales calls from bajaj finance. Although, every time i request them to not call again, this is not stopping at all.
They call from various phone numbers and that too during office working hours.
This is too very irritating and annoying.
They need to understand that this kind of marketing is disturbing one’s privacy.
Please help in getting rid of these unsolicited phone calls.