Shocked, new cellphone lasted 6 days

I bought a new cellphone Vodacom P520 on 8 October 2018. Checked the phone and it worked, the phone worked for 6 days, then it stopped working, blank screen,the 7th day was on a Sunday, i returned to Ackermans the Monday to hand in my phone. The phone was sent away to SMD Technology services for repairs, almost a month later now and they say it has water damage. And it will cost me to have it fix, How can this be, I only had 6 days of use of this phone, and now i have to pay to have it fixed. This phone was never near water, There is no way i could have caused water damage. And now i am without a phone. I want a replacement.