Pay back the money

I bought a blender in December 2023, it was faulty they send the Driver to collect it. On the 21st of December 2023, they told me that I must send account details for refund. Of which I did send them my bank statement for account no. I was told it will take 7 working days for me to get my money back. Since then I am still waiting for my refund. 7 days has passed long time.. I don't know if this is how they rob their customers or what.. All I need is my money nothing else. How long must someone wait to get her money back.