Incredible Connection is not credible

I bought an iLife tablet online and on delivery I realised that the sim slot could not hold the sim card. I sent it to Westgate branch on the 27th September 2021 and I only received it back on the 17th November 2021 after a lot of follow ups and I initially expected a response in 14 days. When I open it a pop up message appear that the storage is full and it doesn't open it only shows "android is starting". When I go to settings and check I realised that someone was using the tablet because it is full of photos; videos; music and apps. Indeed the storage is full of photos; videos; music and apps that I never installed and the tablet is not in a working condition. I expected the device to be replaced as I brought it back within 7 days. It feels like a **************** as I bought a new device but now it basically have a second hand because someone has used it. I regret buying this device and I hope they will help me.