Either a mobile number or email address parameter must be provided. If both an email address and a mobile number are provider, the OTP will be sent to the mobile number. If only an email address is provided, the OTP will be sent to to the user's inbox as an email.
When the API is called a record for the contact is created if one does not exist. If the contact does exist, but is deleted the OTP will fail.
The return value includes the contact's unique DailyStory ID. This DailyStory ID is used to validate the OTP received.