Refund not received in the turnaround time given

I always received perfect service from Checkers Sixty 60 , but this time they dissapointed me.

On the 29th of December A product from my order was out of stock, a quantity of 4, so I selected 4 other replacements.

When my order arrived, I only received one out of the 4 replacements. I phoned the help centre right after I received the order. The guy said that they will refund me the 3 products I did not receive , in 24-48 hours. Today is the 8th of January, and still did not receive that refund into my wallet on the app.