Airtel — misbehaviour of your staff abusing and threatening on phone

Address: 302 concord, 208002

On 22/01/20 there were many calls from [protected] by a staff of airtel, questioning me, why i did not continue with air tel wifi service provided. I informed that it was not attended by any one and we were not getting services so i dumped it and using other facility.
He was abusive and threatened me, that my running mobile no will be dis connected.
It was serious illegal threat and any consumer cannot be threatened like that.
Will you pl take up the matter with m, d or i should file a case?