Cell phone network unavailable for outgoing calls and sometimes incoming MTN port elizabeth

We need urgent help in our suburb in Walmer Heights Port Elizabeth. For the past year we cannot make any calls , there appears to be problem with the tower, we pay huge cellphone bill but the entire neighborhood is complaining, advising as far up as senior management but nothing ever changes. Can this please urgently be investigated as it is a security issue not being able to use your cellphone.