"Sorry, Supplier (Supplier Name) does not provide delivery in your area, we apologize for the inconvenience. Please contact the supplier directly to arrange alternative methods."
Suppliers can choose where they want to be displayed, the way ONEzoo calculates this is on your delivery address and postcode.
The first remedy is to go into your account information, and update your address and postcode. If it looks correct, just re-enter this information.
Failing this contact your supplier and ask them if your location is acitvated in their delivery areas.