Samsung note 10+

I bought 2 note10+ in October 2019 from MTN and the phones gave me problems within 2 months in my possession. I took the phones to Samsung the Groove Mall and I was advised that they will try and fix the problems and if the problems continues they will replace the phones. They fixed the phones but the problems continued and now at Samsung head office escalation department a lady by the name of Kgolofelo says they are not going to replace the phones as they have past 6 months and I should have told the guy from Samsung the Groove Mall that I want my phones to be replaced and not fix even though they said they will replace the phones if the problems continues. Kgolofelo says I shouldn't have not taken the advice of the sales person. Yooooooooo Samsung!!!!!!!!!!!!!!! And I was told I can take the matter forward if I want to.