Return product rejected, not returning my unopened goods

I returned an unopened / unused 5l bottle of 4-stroke motor oil, which was collected on 6 March 2023. The order return showed concluded on 9 March 2023, but I didn't receive store credit so I emailed on the same day and received a reply on Friday 10 March 2023 saying that it's past 7 days and they will return the product to me. However , no update had since been received, I sent other emails following up on the tracking number or when I will get my product back (as it was unused). Please can someone get back to me urgently.

Ref: MRRN-6VZGM-6XE8