Hey folks.... I am currently testing around with carrierService requests to a callback_url to fetch shipping rates for the checkout but unfortunately i do not see any requests to my url and shopify sets the shipping rate to the value i set as fallback.. when i POST to the provided url, i see a response which looks as described in the docs. what am i doing wrong? any hints in general or could someone help me perhaps with some logfile insights (can send you more detailed data in that case if required).
Is CCS enabled for your store? If yes, check if there are any errors when you create your CarrierService during app installation.
With shopify plus, would guess so, yes. I can see the app entry in my setup of shipping rates, other "manual" shipping rates are removed.