I have this problem when trying to send a flow from the interface, it tells me that an error has occurred while sending a message but it does not tell me what it could be
Hi Julian,
Could you please verify the following: - Flow JSON is valid - Sender phone number is registered with Cloud API
If you are still facing the same issue, could you try sending it through Cloud API directly (see https://developers.facebook.com/docs/whatsapp/flows/guides/sendingaflow#userinitiated)?