Bad service and told to take damage TV

I bought a 58 inch sansui from hi fi corporation in woodmead. I found a line when I arrive at home after plugging the TV. The next date I went back to HIFI to return the TV. The manager was very rude and she told me where to get off. She said I can go where ever I want they will not assist me. She even gave me the telephone numbers for their head office and even told me to go to ombudsman. What a manager. Then later someone intervened and they booked my TV for repairs. Now after 21 days they told me that the TV cannot be repaired I must come and take a none working TV WOW. I spend money to buy something which is not working. What BAD SERVICE AND BAD ATTIDUTE BY THE BRANCH MANAGER