Twilio SMS message Not Delivered with unknown error

Question

We're having this weird problem with Twilio SMS messages hanging with status.

We have tried sending from different Twilio phone numbers to make sure it isn't a problem with that particular number being blocked and none of them go through.

Our system uses SMS messages in the standard form of two-step authentication with a code and a short message to the user inside the SMS body.

The carrier that the message sent is failing is Tune Talk (A Malaysian one).

The error in the Twilio Logs/Console I see is:

Status: Undelivered
Error: (Error: 30008) Unknown error. None 

Message SID if it's in any way useful is: SM1024a2d519cf4f6bbfcbc838587cb2af

Any insight on why this is happening would be greatly welcomed.

Answer 1

We had also the same issue with phones that used to receive messages. The problem is carrier blocking/filtering. Every carrier uses different filters.

Some carriers block messages with 90% the same content, others use rate filtering (1 message per second or more) others use a combination. The blocking is not forever thought.

Twilio gives the following possible solutions:

Check that the phone you were sending to is turned on and can receive SMS

1. Ensure that the phone is not roaming off network. We cannot guarantee message delivery on roaming phones.
2. Try sending to other phones who have the same mobile carrier. If messages to other phones go through, the issue is likely device related. Try rebooting the device or contact the mobile carrier for help.
3. If you are sending SMS from an alphanumeric sender ID, see if using a Twilio phone number works better. We’ve observed that certain networks may block alpha sender IDs.
4. Try sending a shorter message to the phone, with simple content that does not include any special characters. This would give our support team an idea as to whether the failure is related to concatenation or character encoding.
5. Twilio support can help investigate what went wrong with our carriers. Please open a support request and include a minimum of 3 or more message SIDs where a 30008 error was thrown. Per our carriers' requirements, these SIDs can be no older than 48 hours at most.

Check -> Error 30008

Another solution is to use a 5digit code phone number.