No Refund policy

I bought a ring for my wife on 7 October 2022 as a surprise gift for our 23rd wedding anniversary, subsequently she didn't like the design and we tried exchange it for a refund. Litte did I know the store had a no refund policy or so they say. When we returned to the store we were told that theres the sign and on the receipt is written no refunds. When asking the owner for a policy of their sign, she said there is no need for such. My question is, if no one made me aware of this and sold me the item, I was sold under false pretense?

There is nothing we want to exchange this for in the store but is now forced to take a credit note or keep something we dont want. Businesses like this should not be allowed to operate without being submitting to the CPA otherwise anyone can just wake up one morning and decide they operating under their own business laws.

With this said, I tried reasoning with the owner herself but she is unwilling to reason or refund my money.