Lost Receipt

Today I went to report my Laptop to claim. Warranty I have this laptop for almost a year bought it last August, the lady there claimed can't help as I don't have a receipt, told her I lost my receipt while I was moving back home since I was retrenched the same month but I have my bank Statement to show, maybe they can try to go back on the date and find that transaction, she said help without the receipt now I have a laptop that's hardly working properly ?