Samsung Mobile Horrible after service

Good Day

It's been almost 6 months that Samsung lost my S9 plus device via courier service, I had to book the device twice because of it being faulty. Since last year Oct/nov 2018 I have been struggling with Samsung and Mtn to have this matter resolve, every time i get empty promises from Samsung that they'll resolve the matter, i was promised a new device last year within 48 hours, never happened. then i was told to wait until the claim went through so i said no, i don't want it. I phoned Samsung and Mtn and emailed them about 100 times through out this period I stopped the debit order in Jan 2019 and forwarded i cancellation letter to Mtn stating that I won't be paying for a phone that I don't have in my possession, yet I am still waiting for Samsung to notify me of what is happening and yet I still haven't receive a new device or an upgraded device. Samsung refused to pay the cancellation fee, today I received a call from a rude MTN assistant a ********** 686 no. This Lady tells me she is handing me over to their lawyers and i must pay no matter what, so i told her she must phone the mtn store they have all the information she tells me she will not i must sort out my account, i am in a 30 day arrears, but I have been with out a phone for 6 months but MtN demands payment. Yet it shows MTN doesn't care about their clients, same with samsung no after service!!!! I had to take out another cellphone contract because I cannot be with out a phone. What am i suppose to do, just pay for a service that I dont get, a service where Mtn can treat their client like dirt, and samsung lost the phone but I have to smile and be happy and wait and wait and wait for a new device until they decide when it's convenient for them to sent a device of their choice, the client don't have a say what so ever as long as the client is paying everything is fine and the client must be happy with the disgusting service. When I contacted MTN, Mtn even told me I must Pay, and take Samsung to court, I must pay my contract an be a good little client and pay and pay even though I don't have a device!!!! Please will someone advise me what to do? Ref no ********** 715