Lay bye - Consumer Complaint for PEP STORES

I lay byed a cellphone at pep cell Dwars loop mall and it expired I went to the shop n told them that I lost d receipt I gave them my I'd n they found that the laybye expired n cancelled n I said with my money can I take something they told me to make an affidavit stating that I lost my receipt which I see is not far is this the company policy cause in d receipt there is no clause talking about affidavit. Pls assist and advice