Bad attitude toward a customer

I would like to inform management of sportscene emba mall to sfiso one of their teller back to training because he don't know how to treat customer's , this morning I went to buy a t-shirt one of the lady was helping me to choose I ask her to fit it she said I must go to pay then when am done paying she will help me with fitting I did as I was instructed , after done with payment Sifiso refuse to allow me to fit the Tshirt cause I fail to produce my Identity number during the payment ,since when now we should produce the I'd document when buying clothes with our own money it's been a years with sportscene but the experience I got here at a emba Mall shop 39, cnr embalenhle Ave &OLD PROVIN , it makes me fell so small