No Customer service

I have recently had a landline installed(August) for my 93 year old mother in law who is in a retirement home in Bryanston and I cannot phone her from my landline at home in Honeydew or from either of my sister in laws houses(which is why we put the landline in in the first place) we can only phone her from our cells.I have reported it 8 times up to now and all calls have been closed as fixed.I have also spoken to 3 supervisors the last one being Sabelo last week who promised to call me by yesterday after his investigations.Guess what no call.I have also phoned the call centre at least 25 times and either get cut off or they put down the phone.I have also been charged for a callout(what a joke)So what do I do NOW to get the service I am paying for?Very unhappy customer.