" unable to load subscripton options" please check your connection and try again (dismiss)

Hey ​@luca-carnevale-90dcdf - from what you describe, this seems to be related to failing to load offerings. Have you checked our section on the recommended steps to fix this: https://rev.cat/why-are-offerings-empty

Some common culprits are the Apple Business and the Developer Program agreements that need to be validated in App Store Connect. 

Just to confirm, did the whole flow work as expected during testing and with the API key? Or Sandbox was also not working as expected?