Transfered 7 times and no solution

I called on behalf of my 73 year old grandmpther to get her wireless fixed landline sorted, as we cannot call her from our cellphones as there is a problem with the line. I called and got transfered from department to department and not a single person logged a call or tried to solve the problem. I spoke to 8 agents and not a single person even tried to solve the problem. So now its still impossible to make calls to her landline. We have been trying to get problem solved for 4 months.