[Resolved]  Croma — Harassment

Dear Sir,
Please do bear with me.It is a long mail but needed to explain the gravity of the situation.
I had purchased an airconditioner from Croma(Hadapsar,Pune) last summer in May.Due to a defect in the piece we went for an exchange.The new piece was sent to my residence in a few days but the defective old piece was not collected. For three months after that we were after them constantly calling them to take the piece out of my place.But they never turned up,Always saying they would come the next day.Then the rains came and we had to move the heavy outdoor unit, which was left on the open terrace,ourselves and on calling them,again they said they would come the next day.
In between they had called on 2 occasions once was 4 months after the piece being left behind saying they were on their way to collect the piece but we were in goa so couldnt open the door for them.On the 2nd occasion 2 months ago they called at 8.30 pm when my mother was alone at home.She told them to com the next day.They didnt turn up.
Yesterday though when my sister was alone at home and me and my mother in mumbai for a hospital visit, 4 men(without IDs or uniforms) turned up at my house banging the door and shouting loudly to open the door.Despite of her saying we were out of town and to come back in 2 hours (as we were on the way anyways.),they kept harassing her for over an hour.They claimed not to have cellphones to call me and speak to me and refused to leave the premises.Finally my neighbors had to intervene and hunt them away but not before those 4 men threatened to bring 'people' and 'deal' with them.This behaviour is intolerable.
Please do advise me on a course of action.Am I under any obligation to keep a product in my house? What is the legal course of action i can take?
Please do advise me,
Francis Araujo.