Negligance and poor service

On the 11 of February 2015 I made a purchase of Bluetooth headphones. Later the same day realise that the was something faulty with the head set, the following day on the 13 of February 2015 returned the set to the store, while we were waiting for the manager to authorise the transaction, other customer stole my headset on the counter while I was waiting for David Far. The most irritating part is the fact that since then David the branch manager have failed to call me and update on his progress concerning my matter. Called him on the 16 February 2015, to asked because on our last conversation he promised to look up on the transaction on the stores database and call the cctv guys to do the lookup. His only concern was why did I **** and said I made an cash or card purchase while I did neither. As I made the purchase using my funds I have by them which were deposited by my company. Up until today my matter has not been resolved.