get https://sms.8x8.com/api/v1/subaccounts//messages/
This resource can be used to query message details like delivery status using the unique message identifier (UMID) of the message.
URL
You need to specify the sub-account id and the umid of the message in place of {subAccountId} and {umid} respectively.
umid is the unique identifier you received when you submitted the message to the API.
API Rate Limiting
To protect the platform from being overloaded and maintain a high quality of service to all customers, we enforce API rate limits for this API endpoint.
The limit is set to 1 request/second per subaccount.