Sim problems

My boyfriend has been having problems with Telkom for months now.he took out a phone contract last year November,along with this we found out that whenever we call the phone that it says “The number you have dialed does not exist” you have literally got to phone him 10 times or more just to get through,he also does not receive sms or is not able to use his internet services.To be honest we have been to every Telkom store in the Western Cape,done 5 sim swaps,spoke to the useless technians in store who are of no help and clearly have no idea what they are doing(don’t even get me started on their call center staff)We have tried the other sims in the phone to rule out that it is not the phone which is the problem(which is exactly what we tried telling those *********** staff) we also put that sim in another phone and it does the same thing(obviously meaning there’s a connection fault on between the sim and Telkom network)which they have not figured out yet because up until today 10/06/19 - 7 months later they have done absolutely nothing to help us we pay every month for a useless services.Their call center technical support never calls backs nor can they give us a turn around time as to when the problem will be fixed - if ever (all they keep say is the problem has been escalated)ESCALATED TO WHAT?!**** services!!to ****ter service!!!Absolutely horrified that this is the way Telkom treats their customers and that we have been sitting with a problem for 7 months paying the contract without fail for a service that we cannot use.