The destination number you are trying to reach is unknown and may no longer exist.
The device you are trying to reach is not on or does not have sufficient signal.
The device cannot receive SMS (for example, the phone number belongs to a landline)
There is an issue with the mobile carrier
Possible Solutions
The first step to troubleshooting this issue is to attempt to replicate the problems. Attempt to send another test message to this user via a REST API request, or through the API Explorer in the Twilio Console.
Pay close attention to your request and double check to verify you are attempting to send messages to the correct phone number in the correct E.164 format: [+] [country code] [subscriber number including area code]
If you see similar results, continue troubleshooting with the following checklist:
Is the destination device powered on?
Does the device have sufficient signal? If not power the device off, wait 30 seconds, and then power it back up.
Is the device connected to the home carrier's network? We cannot guarantee message delivery on devices roaming off-network.
Can the device receive non-Twilio SMS?
Can the device receive messages from another Twilio number (non-Alphanumeric Sender ID), or with a shorter one-segment (non-concatenated) body?
Can other devices using the same mobile carrier receive your messages?
Continued issues with Error 30005
Twilio's Support team can help investigate what went wrong with delivering your message. Please collect 3 or more message SIDs in your SMS logs from the last 24 hours that were flagged with Error 30005, and open a support request.