Why some text messages don't get delivered

When you send a text, it passes through several stages before it shows up on someone's phone. Here's how to figure out where things went wrong when they do.

Stage 1: Did the message leave 365 Agents?

Check the status in your dashboard. If it's "Sent" or "Accepted," the message left our platform. If it's "Failed" or "Error," it didn't, and the error code tells you why.

Stage 2: Did the carrier accept it?

Sometimes we accept a message but the recipient's carrier rejects it before delivery. Common reasons:

• The recipient's carrier blocked the content (classified as spam)

• The recipient's number isn't a mobile number (landlines generally can't receive SMS)

• The recipient's number is invalid or disconnected

• You've hit your daily brand cap for that carrier

Stage 3: Did the recipient's device receive it?

Even a successfully-delivered message can fail to show up:

• The phone was off for an extended period (most carriers store messages for 24–72 hours, then drop them)

• The recipient individually blocked your number

• The recipient uses a third-party spam blocker (RoboKiller, Nomorobo, iOS filter) that suppresses unknown senders

Stage 4: Did they see it?

Some phones put messages from non-contacts into a separate "Unknown Senders" folder the recipient rarely checks. Common on iPhones with "Filter Unknown Senders" enabled.

When to contact support

• Delivery rate drops below 90% across all recipients

• You see consistent rejections with specific error codes

• Messages appear accepted but recipients tell you they never received anything