To be transparent about what happens to your SMS message in the delivery process, we share return codes (also known as error codes) with you. These return codes are part of the “buffered notification,” a temporary DLR (delivery receipt) that is sent one time shortly after you send the message, in case the message is not delivered instantly. The return code is also part of the final DLR that we share with you in the case of successful delivery, failed delivery or when the validity period of the message expired. Check here for more information on return codes.
If a failed delivery occurs, we recommend that you check the validity of the receiver MSISDN (mobile phone number) (and confirm that it’s in the correct format, including country code). Our product Number Verification can help.
Our customer portal my tyntec contains the message tracking module, where you can search for messages via messageid — and other parameters — and see the message status.
If you have additional questions, feel free to contact tyntec's support team at firstname.lastname@example.org