deductions on cancelled contract

On 2018-02-19 I made an online application for a Wi-Fi Router, and I was called by the call-centre to complete the application. The contact is for Huawei -E5573s-606 Router Smart internet at R139.00, however for the first 6 months I will receive 10G Data and 5G for night surfer. I was also told that my area Soshanguve has Telkom network coverage. On 2018-02-26 I received the router via Courier IT, I tested the device while at work. on my arrival at home I struggled to use the device.

on 2018-03-06 I called the call centre regarding the network coverage and the extra 5G data not received. I was told they will get back to me. I re-called again on 2018-03-09 was told the matter has been escalated. I called again 2018-03-12, where the agent told me that my area does not have network coverage and she does not understand why I was given the contract. I then requested her to cancel the contract under the cool off period my complaint was not being attended too.

She told me that the contract was cancelled, no deduction will be made and they will fetch the device. The device was collected on 2018-03-20 by Courier IT.

Telkom deducted month-end March(R200.68) and again they deducted this morning an amount of R349.68.

I need clarity on the matter as I cancelled the contract within the cooling off period.