Replacement of a new battery

Kindly note that I have bought a new battery at battery center Mafikeng on 11 November 2019. I have experience battery problem on 29 November 2019 until to date. When I check the battery today on 03 January 2020 I found that they put BMW battery on my car. The battery on my car and the description of the invoice are not the same. I tried to call them and they are not pick up the calls.