Maponya Mall Edgar's pay joy

Edgar's Maponya Mall Basetsana the cell phone consultant sold me a Huawei Y70 smart phone on the 19th of October 2022, the cellphone was sold under the impression of paying the 30% of the actual price of the phone which was R3999. The 30 % was paid which is R1199. 97, then I was told that I couldn't take the phone back home since they needed to install some software. Completion of installing the software the total amount owing to Edgar's through payjoy is now R7450. I requested a breakdown of the mark up, requesting for a clear explanation on how did the price move from 3999 to 7450, both Basetsana and her supervisor could not break it down, she responded by saying she is still new and that she knows nothing, I should call customer care and ask them. Mid day today when I called she couldn't give me answers and referred me to someone by the name of enerst. I called Enerst and he couldn't give me answers as well but told me he will call me back.

Hello Peter may you please assist in this matter as I'm being sent pillar to post, I'm intending to take back the phone tomorrow as they told me today that my instalment is due on the 26th of October 2022 which is next Wednesday.

This is false sales and I'm worried about my credit profile.