Long wait for product ordered unacceptable.

I placed an order on line from 04 March 2025.Paid for it via my card, payment accepted. Supplier promised from their advert that delivery is from four business days to about nine days should there be customs delays. I have not heard from supplier since payment was taken.No delivery came.It is the 24 March 2025 , today ( 20 days later) no delivery of the ordered product has been received. This has made me panic and concerned of whether these people are who they say they are.Genuine business people selling proper products. How long must I as a client wait without any form of update regarding this order?