Poor and bad Service. Told manager is always away

Purchase a Telefunken TV 58'' still under warranty up to 2020. TV stopped working. 21 days repair period is over its a month tv went for repair and promised to receive a new set. Now being pushed around. Please needs urgent help. Without tv for a month. Store technical manager always say no stock in Gauteng which is not my problem. Agreement states after 21 days new TV. Need to be checked out for bad service and poor communication. No calls from store. Always I must go to store and no help at all.. Regards Bad Service and don't keep to agreement