Exchange for a working speaker

On Friday 31/07/2020 me and my husband bought a portable speaker for our son for R200 and we didn't keep the receipt/slip because we didn't have any intentions for taking it back, but unfortunately when we got hope the speaker was not working and we couldn't take it back on the same day or the following day because we stay about 100km from the store, we were able to return the speaker on Monday 03/08/2020 but unfortunately they refused because we didn't have a till slip, I'm hurt and disappointment about the service because u could see that the speaker was never used, so now I'm sitting with a speaker that is not working of which I have paid R200 for, its sad because it's not like we wanted money back all we wanted was a working speaker, WAS THAT TOO MUCH TO ASK.. FOR