Disappointed in order return process.

I bought over the phone a new laptop contract which comes with router. I received my order on Monday the 25th and on the 26th I realized the router charger isn't working, I even tried on my cellphone to confirm. I called the same day to report and was told the agent who sold me a contract will arrange an exchange I was told to leave my contact and they'll send the message to her. I never got a call and decided to call on the 27th Wednesday I was told the same thing until now I've never received a call. Today it's the 28th day 4 and they say you only return within 7 days. What am I supposed to do? Imagine everyday being told they'll ask the person who sold you the device to call you. So you're only important when you place an order and after that you'll you're treated like you're not even gonna pay? Wow Vodacom! So if the person who sold me the device can call in sick or quit it means I'll never get help. I'm so disappointed that I do t have the energy for this.