Urgently need receipt back

Good day Last week I bought clothes worth R3154, today I went to exchange something worth R155 for something else at Pep Store Dyzenze Plaza (Mpumalanga) and was told I cannot have the receipt back. I asked them to make a copy for me and they told me they dont have a copy machine. Please I need assistance with this, I need the receipt back for personal claims. Kind Regards Andiswa