App not appearing in "Use carrier or app to calculate rates"

[jessica_grav]

Bit of background:

We are partnered with a client to build an app that does calculations on shipping rates.

The partner has a user of the app that is having issues getting the app to work.

When the app is installed in a store, a carrier service is created via the carrier_services API endpoint. In our development environment, the behaviour works as follows:

1. When the app is installed, all existing shipping zones receive the new carrier service and get a new record saying (Rates provided by app)
2. New shipping zones do not receive the new carrier service. To add it, you can either reinstall the app or go Settings > Shipping and Delivery > Manage Rates > (On your new shipping zone) Add Rate > Use carrier or app to calculate rates and select the App from the drop down

It also works this way for our client partner.

The problem: One of our partner's users is unable to get that carrier added in any way. Installing the app does not add it. And when manually adding (via step 2), the app does not appear in the dropdown despite the fact that it is indeed installed.

What could be the potential causes? Is there perhaps a store specific setting that might prevent apps from managing shipping?

The merchant has confirmed that third party carriers is allowed on their account.

[Luke_K]

Hey @jessica_grav 

I'm wondering if the specific store that attempted to install the Carrier Service app meets the conditions outlined here? The app's request to create a carrier service using the Carrier Service resource will fail if the store doesn't meet one of these conditions below :

• It is on the Advanced Shopify plan or higher.
• Its Shopify plan is paid annually.
• It is a development store.

Let me know if that helps at all! Thanks!

[jessica_grav]

Turns out it was a caching issue.