Inflexible returns policy for a unique case

Really disappointed with your after sales service at Cape Gate. 2 months ago I bought a Lenovo laptop for my small office. Returned it 8 days later due to blue screen. Told 6 weeks for an inspection (missed immediate return by 1 day). Was told 2 weeks later (nice!) we could get a replacement. Original product was out of stock so we got a lower spec Lenovo and the balance on a Gift Card (not so nice). 3 weeks later this laptop will not start. I returned to Cape Gate again, to be made to wait 15mins at returns for a salesman to appear. After going inside, I was told 6 weeks again for an inspection, to which I requested an immediate replacement with a different brand, as we cannot wait another few weeks for a product that was paid for 2 months ago already. The salesman escalated it to his Manager who then politely escalated it to the General Store Manageress I assume. While initially polite, she did not take into account the unusual circumstance (2 laptops giving up in quick succession), but refused to accommodate what I believe to be a reasonable request.<br> Some response from the Call Centre (who didnt phone back) or Store itself would be appreciated.