need exchange in device

Been a customer for almost 6 years now, on Monday 19 October 2020 I took up a new contract phone Huawei P smart S phone , at centurion mall, It was explained the mobile device now uses HMS and no longer GMS , the explanation was not comprehensive in terms of what I would be losing from switching from GMS to HMS , I called the call center and was told I still have 7 days to return the phone since its in the cool off period, today 22 October 2020 before work I went to the store were the phone was purchased Centurion mall Telkom.

The consultant told me I can not return or exchange the phone because nothing is wrong with it.

All I want to do is exchange the phone with another of the same price, is the cool off period no longer applicable ?

Am I now forced to pay a 2 year contract for a phone I'm not happy with ?

If so this will be my last contract , I have never had problems with Telkom until now.

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