Pep cell Galleria Mall Refused Phone Exchange

Bought a phone from Pep Cell Galleria Mall Amanzimtoti on the 3rd June 2021 but I realised at home the phone doesn't run 4g network and doesn't want to install apps from playstore. Took it back next day for another one but the Manager of the shop refused. Said it was my negligence! Totally disappointed!! Shop sucks