Bad Service

I write to you to raise my complaint concerning the service support i have received from game store Eastgate branch(G095). I purchase the above mentioned item(Lenovo laptop) on the 21st December 2020 and the laptop package was opened in store by a sales representative Ephraim Sethabathaba to indicate that all related items to the purchase are in the box. further to that the laptop was not tested for functionality. Upon setup of the device it has been discovered that the keyboard is malfunctioning. when i returned the goods within the specified 30 days as stated over leaf receipt that the goods can be returned for refunds or exchange i have been denied purchase clause with the store manager using his power over my rights to get a refund or another laptop. To which he opted for a repair, my concern is how can a new purchase be repaired. To that end i was not given good service i need the laptop urgently as the schools are opening on the 19 Jan 2021 and cant wait for 21 days for repairs on the new laptop. The laptop has been tested in store and it found to be not working then why should i wait 21 days. He gave me no choice but the unit for repairs as he says he cant refund or exchange it due to the seal been broken for which it was broken in store.