SMS has not been received

What is the reason if your SMS does not arrive?

SMS may not arrive at the destination device for a number of reasons. We will talk about the following in this help article:

If your SMS does not arrive despite these measures, please contact our support and tell us the ID of the SMS or the recipient number and the time of sending. This way we can quickly understand what the reason for the missing delivery is and help you.

 

Checking the status report: Did the SMS send?

First, check the status report of the SMS in question. This will give you a first hint as to why your SMS did not arrive. If your SMS was sent, please continue reading at the respective status report in this article. If your SMS was not sent, please check if there is enough credit available, if you accidentally tried to send your SMS without text or if other invalid information could have prevented the SMS from being sent.

 

Status report "Delivered"

If your SMS has been sent, you get the status report "Delivered" and you are sure that the SMS has not arrived, for example because you have sent an SMS to yourself, please check if:

  • The recipient number has been entered correctly (also look for typos).
  • You have entered the correct country calling code.
  • The receiving device displays the SMS after a restart.

If these points are fulfilled correctly, please contact our support and provide the ID of the SMS or the recipient number and the time of sending.
You can see a screenshot showing where to find the ID at the top of this article.

Status report "Not delivered"

In most cases the status "Not delivered" has something to do with the receiving device.

If possible, check the following:

  • Is the receiving device switched on?
  • Does it have network reception?
  • Does it receive the SMS after a reboot?
  • Can the device currently receive SMS that were not sent via our gateway? 

Status report "Rejected"

If you receive the status "Rejected" the message was rejected by the network operator. This can also have several reasons. Often, the filtering of messages is related to the regulations in the recipient country.

Unfortunately, the international market is very inconsistent. We have a blogpost on sending international SMS where we offer an overview of the rules. Nevertheless, please check the regulations in the recipient country carefully, as we cannot guarantee that the list is complete. Some countries, like France, the USA or India have very complex and strict regulations and may impose massive penalties.

The most likely reasons for your SMS being rejected are the following:

 

The content of your message was identified as spam

Countries allow you to send different content via SMS. This means that in some countries, the network operators' filters automatically filter messages that contain certain words. In China, for example, content that deals with cosmetics, among other things, is forbidden. 

Also, if you would like to send links, check if sending URLs (links) is allowed. Some countries prohibit this completely or allow it only if you register in advance.

Your sender ID was not accepted

Again, this is usually an international problem. Depending on the recipient country, it is possible that only a specific kind of sender is allowed. This means that alphanumeric senders may be blocked or numeric senders may be changed. In addition, in some countries it is necessary to register as a sender in advance.

Encoding

Message encoding also plays a role when sending international SMS. Certain network operators (carriers), for example, will not process Unicode messages. In addition, you must observe the various rules regarding the length of the message here (see next point).

Length of the message

The length of your message may also be the reason why a carrier rejects the SMS. Again, the different rules of each country are the cause. Depending on the coding, certain countries allow fewer characters than usual. In China, for example, an SMS can contain a maximum of 65 characters in Unicode and a maximum of 130 characters in GSM coding. In other countries, long SMS that are concatenated are not supported.

 

Complaint/Refund

If you have looked into why your SMS did not arrive, you can issue a complaint about your SMS in your logbook in the account at any time. To do this, please click on the information icon next to the respective SMS and then on Reclaim. Our technical department will then see the data of the respective SMS. Therefore, we can intervene accordingly and, if applicable, give you a refund.

SMS contains blocked links

If your SMS get rejected, it is also possible that the links in your message have been blocked by our filters. If you believe that your SMS did not arrive due to a blocked link, please contact us.

 

Inbound SMS do not arrive

Please read the article "Inbound SMS do not arrive" for details.