Worst service

I bought a kitchen mixer on the 26th January 2022, only to find that it would not fit my kitchen set-up. At which I went back on the 27th Jan to exchange but I was told that I could not RETURN items on sale.

I need to EXCHANGE, for crying out loud, not RETURN. A mixer is not like a pair of shoes or a shirt that you can pass on to the next person. The invoice stamp says NO REFUND and does not say anything about an exchange. How sick is that?