jam jam clothing not a retail outlet but loan sharks

I bought an item on jam jam stores in pretoria (Bosman satation mall) I wanted to exchange the item because of a wrong sixe. unfortunately I was not allow to exchange it to different because I didn't have a receipt I can only change ro same item; the fustrting part is I cant exchange the items bought to any any other item in the stores but the store does not have my right stores, they called other jam stores around pretoir and still coildnt find the right size.

Jam Jam Clothing not a store but loan sharks!

Manager Pleasure Masina at Jam Jam refused to exchange items bought / cash refund.

the manager did not give me update while checking with other stores, I had to ask/demand feedback, she was relying on WhatsApp group chat!!!kept on saying she cant help me without a receipt but she was willing to assist with a receipt if I was exchanging with the same item; I find it very ridiculous and bully. you cant choose for me what I buy n don't buy with my own money

they don't have my size in store or surrounding stores. how Is that my fault. they dont cash refund which is okay I don't want cash refund but to exchange, now they dont have my size but refuse to allow me to take anything of my choice. I was send back with the items. what must I do with it. throw it away? I paid good money for them. Jam jam clothing is either i'm allowed to exchange to anything available in store or my money back

regards Clara