Fulfillment Service Location unable to add carrier service

8 0 1

We have a shopify app that creates a fulfillment service. This in turn creates a location. When I try to create a delivery profile and assign it to this location, I am unable to add carrier services (USPS/UPS/DHL). When I go manually through the interface of our test stores and try to create a shipping zone using our App's automatically created location from a fulfillment service, it also does not show USPS/UPS/DHL as options. I have tested with a manually created location and it works fine, allowing me to pick carrier services. I can't find any information about why this is happening online or in the forums. Anyone know how to get around this?