Mutli-Vendor Marketplace: Adding postal codes for shipping

[aleenahhassan]

Hello, I'm using the multi-vendor marketplace app for my store. I want to set up postal codes for my store according to city so that vendors can set their shipping rates per city. When I tried adding it via csv, it kept saying that postal codes must be unique (although they already were unique values). I tried putting in the numbers into the example file they provided. Could I please get some guidance to upload postal code zones for my shipping rates?