False adverti*****t on brochures and website

Good afternoon, on the 5 August 2020 I went to Mtn Pinecrest for laptop deal that I saw on mtn website that was advertised for R299pm for 24 months HP laptop with 20 gigs. I was assisted by Kristell Collins. When I show her the deal that was interested on she told me that they don't have it but instead they have on 36 months at R449 pm. Then I reverted to check what they had on the brochure and I came across a Lenovo IdeaPad slim for R299pm for 24 months 2gb and she confirmed that she had that on stock and I said I would like to apply for it and while she was busy with my application it turns out that that deal comes up as 36 months not 24 months as advertised. She called her manager to show him and they advise its an error... And my question was how can they false advertise and if it was an error why they never picked earlier that was a mistake before we can come to the store and apply for the deal and get told its an error worse of it even mtn deals were errors according to them cos I even showed them on the website. I asked they to send a lodge a query on that price as I wanted that deal and I want it with the advertised price because as a customer I can't be responsible for some incompetency and failure to authenticating what's has been advertised. Firstly they refused to lodge my complaint because they insisted that it was error then I told them that it's fine I will take the deal but I will lodge my complaint myself then eventually they said they will phone their regional manager of which I waited while they were calling then I was told they have sent an email and the turnaround time is 48 hours, 48 hours passed no reply from Kristell and I sent her an email to do a follow up... Then today she sent me an email if I'm still interested on a deal it's 36months of which she told me that they haven't received any feedback on my complain. I'm now wondering if they did send logde my complain if they did why they are not following it up and close my case... Not just to push for the sale that wrongly priced... Mtn must take responsibility of their mistake.. I was gonna understand if it was one mistake but it's seems they advertise mistakes more that the correct prices. I would like to be assisted with this regard. Thank you.