Issue with outcome of supplier cause of problems with phone!!

Good day

I have a very serious complaint. I purchased a Xioami Redmi Note 4 at the Incredible Connection Store at the mall @ reds in Sept 2017. The phone worked fine for a couple of months and then whilst in the car using the GPS the screen went light, started flickering. Then the same night vertical lines started to appear on the screen. I switched the phone off and on but it didn't go away. the following day the icons on the background lost their HD colors, I tried adjusting the colors on the settings but that did not work. I tried opening up the back and removing the battery but could not as it is fixed to the phone. I then googled the problem and saw a lot of complaints about the same vertical lines issue on the xioami phones. I did not let my phone fall and took very good care of it. I also did not let my phone come near any water. It was also in a protective case and had a screen protector on. I decided to take the phone in to the store on 14 Feb 2018, I explained everything to them they said that it would take 10-14 working days and that they would send it off to the supplier. They did not check for any water damage or anything. On 28 Feb I received a call to say that the supplier came back and said that the phone had water damage!??? I immediately called the store and spoke to the Manager Janine. I told her that it was impossible and that I wanted proof. I told her again what had happened and said that I will dispute this! I am not impressed and asked her how to dispute this. I have still not received the photo proof of the "water damage" and it's 05 March 2018 today. I will not accept the water damage 'proof; - the supplier or anyone could have caused this!!!! I DID NOT cause water damage and I WILL NOT accept this. There is a 1 year warranty on my phone and incredible connection needs to honor it!!! I want either an exchange of the phone with a new warranty/guarantee a refund on this phone or an exchange for a different make. Please look at the following link and read the complaints and look at the photos. https://www.google.co.za/search?q=xiomi+redmi+note+4+vertical+lines&oq=xio&aqs=chrome.1.69i57j69i59l2j0l3.5119j1j7&sourceid=chrome&ie=UTF-8 Awaiting your urgent reply.

Regards Benice