When you say "no longer works" with phone numbers outside of the US - do you mean that you require guests to download the August app, and then you can no longer share access with them inside the August app because their phone numbers aren't North American?
Thank you for bringing this question to the Community. I saw that @Shelley159 left you a comment. Were you able to check her response? It might be helpful to get more context and work together to resolve the issue. 🤗