Broken Cellphone

Last year i had to wait 2 months for my new phone. I received my LG G4 on 1 Oct 2015. On March 11 my phone's motherboard crashed. I took it in on 13 March and they said they will send it in. I received a call that they will replace phone. Yesterday 13 April I phoned mtn and they told me that they received my phone they just cant book it out because their systems are offline. This morning 14 April I received another call stating I can come collect my phone. I specifically asked if the systems are back online will they be able to book it out. They said yes. I informed the lady that I will come after 16:00. She said this would be fine. I went to mtn after 16h. Just to find that their systems are still offline. When I said I asked if I can come the gentleman informed me that they go off and on I should have come when they called. I informed him that is not possible as I stay far and I work during they day. I waited a month and yet still nothing. But if u don't pay they quickly cut your line. I demand my phone be delivered to me or I get reimbursed for fuel spent driving 45km for nothing. This is the worst service i ever received.