Troubleshooting Common SMS Problems

July 20, 2017

This post first appeared on

Text messages seem like a sure thing, right? We tend to send them off without thinking twice about their status or delivery order. We expect them to be delivered moments after we sent them exactly as they were authored. As it turns out, SMS isn't so simple under the hood. So in this article we're going to discuss steps you can take to troubleshoot common SMS issues. 

Message Splitting

Texts are split into a series of messages at the carrier level when they exceed their character limit (160 characters for messages that contain only the GSM character set; 70 characters for messages containing one or more non-GSM characters, like emojis 👍). Here's a tool you can use to determine whether or not your message will be split, and how many segments it will be split into. 

Delivery Order

Once a message is split, it's at risk of being received out of order. For example, if the last segment in the series is smaller than the first two, it may get to the end user first since the shorter message is sent the fastest. You can get around this by pre-splitting your messages in your flows and applying a label to indicate the order in which they should be read. 

message order.png

Undelivered Messages

Android Relayer Channels

If you have an Android device, the Android channel enables you to send and receive messages anywhere you can acquire a local SIM card. An Android channel will experience sending issues if:

  • the phone doesn't have a steady internet connection
  • the phone doesn't have a strong cellular connection

Log into your account, navigate to your account page, and then click your Android channel to view performance stats.

Android Stats.png

Twilio Channels

If you're using a Twilio channel and one or more of your messages wasn't delivered, you may be encountering one of the these sending errors

Twilio 1.png

Next, click the "Channel Log" button link to view bring up your sending log: 


You can use your sending log to isolate the issue and make the necessary adjustments.


If you suspect your channel is have trouble delivering messages, click into the log provided. You'll find receipts for each request made, and if an error has occurred you'll see an error code you can bring to the channel provider's attention.