faulty line for 4 months

i have reported my parents phone over the past 4 months, they are pensioners and need a phone but cannot have a conversation as the line keeps cutting out, sometimes every 60 seconds it cuts off and you loose the conversation on the other side, each time someone comes out they say different things but it cannot get resolved and I am tired of paying R300 a month for something that does not work properly. a week ago someone came out and fixed the line inside and said they would be back the next day as the main problem was in the box outside. 7 days later nobody has come or even given any feedback. This is in Bluewater Bay