miphones - great products with terrible support.

miphones.co.za are an online store that imports and distributes Xiaomi products, mainly their mobile phones. I've been a fan of Xiaomi for many years now, having privately imported a variety of their cool gadgets and I've always found them to be of very high quality while also being very affordable. I was very excited to learn that there was now finally a company in SA who could not only supply Xiaomi phones, but apparently provide support for them as well. I'm a strong believer in the motto of "the device is only half the product, the other half being the customer care behind it", and everything seemed promising at first. I placed an order for a phone and it was delivered the following day. I bought another a few weeks later and had a similar fast delivery. Fast forward a couple of months and one of the phones, my one, started to act up. It randomly closes whatever is on screen for no reason. I tried a software update as well as multiple factory resets which made no difference. The phone is still in warranty, so they collected it on the 11th of October via courier. I received it on the 25th of October, two weeks later. In that time my repeated requests for updates as to the diagnosis of the faults and what actions were being taken were ignored. Promises were made to get in contact with me and none transpired into any action. When I started up the phone after receiving it again, the fault was still there, with no indication of there having been any action performed on the phone in any way other than perhaps a software update/reset, which I had already done and informed them that it would not work. My emails to get back in contact with me were ignored and the only way I managed to actually speak to somebody was by looking at the waybill from the courier and phoning the number that they had left as a reference. I spoke to a lady named Diana who assured me (as she had before) that somebody would contact me. This has been going on all day since this morning and at the time of writing this I have had no contact from anyone who can assist me with what the next step would be. At this stage I want either a full refund or a complete replacement of this device, but I'm being ignored. It's really sad because Xiaomi make excellent products and this company is doing a disservice to the brand.