Mondo/MTN *****

I recently received a cell phone and a sim card, which i did not order. I got a call from a courier company with package to deliver, i then accepted the package as I knew that I did not order anything. To my surprise it was an MTN package with all my details as I am already their customer. I was advised to return it to the store. then call MTN. While returning the package i was advised at the store that the phone was order via online channels. Then i was told that i will be liable for payment as this would take over 14 days for the cancellation to be complete.