Upgrade but no device

Horrible service, or non existent service is more appropriate, after recently upgrading to a new contract which was done online on Mtn's site, I received my new Samsung note 10 lite, only for it to malfunction and crash within 6 days of receiving the phone. The very next day I took it into my closest Mtn branch and was told that they would send it to the warehouse and they would investigate and probably replace the device. This was the 25th January. To date no one has come back to me or can give me an answer as to what is happening with the device. I will start paying for this contract at the end of this month for a device I do not have and also don't know if I ever will receive... Then today after I log a complaint on Mtn Customer services Facebook account, airtime was ****** from me, as I had to give them my cell phone number when I was privately messaged by them. I want feedback from Mtn regarding my device and I want proof that I signed for the contract, as I was never given a contract to sign, neither have I received it.