Mtn worse service ever!!

I received a call from MTN informing me that I am eligible for an upgrade on all 3 my contract, hence the lady provided me with options which I choose from and informed me I will get the device and smart watch within 7 to 14 days it's been 13 days now no communication received from them so when I phone I get told no there is no stock so the upgrade was not done OK so who are you to decide for me what I want and what I don't I then asked for a way forward and was told they don't know after 10 years never missing one payment this is the **** service I get