Refusal to take the device back within 7 days

I visited the store on the 04/11/2015 to take a contract on the Samsung tab 7. I was told it was out of stock. I requested if they could find out from other branches if they have stock. I was told they cant.<br> <br> The sales lady convinced me to take a tab 9 which I was doubtful about. I tried using it on the 5th/11 it not suitable for the nature of my business.<br> <br> 06/11/2015 went to request if they could change the device to a smaller one. I will keep the contract as is. they said I must call customer care. customer care informs me that they have to take the phone back as they can not charge me any amount of the contract if I cancel it within 7day. I feed backed vikash on the info from customer care during our conversation he start screaming and shouting at me stating that he has escalated my query to the are manager who early was in a meeting when I request that they contact him/her and now they are on the road driving. <br> <br> I am appalled by the manner I have been treated by the branch manger never once did I raise my voice with him. I was promised that the area manager will call me till now there is no feedback.