Do not contact me mutiple time for the same cell upgrade !!!

My contract was up for renewal and I was contacted about 4 times and my contract was set. For my phone as well as my mother's phone which is liked to my account. Now I keep getting phone calls abou mtn upgrades. When i tell them the say sorry and put the phone down. Not good enough !!! If I have renewed my contact please leave me alone fot 2 years. Common MTN, You can do better than this !!!!!