Who This Is For / When to Use
This guide is for Kyrios users who see SMS errors, failed delivery statuses, carrier rejection messages, or unexpected SMS charges when sending manual, bulk, or automated messages.
How SMS Delivery Works in Kyrios
SMS delivery in Kyrios occurs in three stages: platform validation, phone number validation, and carrier network delivery.
A failure at any stage can prevent delivery, even if the message appears to send successfully. Understanding where the failure occurs helps identify the correct fix.
How to Find SMS Error Codes and Failure Reasons
SMS delivery errors appear directly in the conversation thread when a message fails.
To locate the error:
Open the contact conversation.
Find the failed SMS message.
Hover over or click the warning icon to view the error message and code.
Kyrios-Level SMS Sending Issues
These issues occur before the message reaches the carrier.
Do Not Disturb (DND) Enabled on the Contact
If a contact has DND enabled, Kyrios blocks the message automatically.
Fix: Disable DND on the contact record before sending SMS.
Phone Number Is Not SMS-Capable (Landline Error)
If the destination number is a landline or cannot receive SMS, delivery will fail.
Common error example:
Error 30006 – Landline or Unreachable Carrier
Fix: Confirm the contact’s number is a mobile SMS-capable number.
Daily SMS Limit Reached
When the daily SMS limit is exceeded, automated and bulk messages pause for the rest of the day.
Individual one-to-one replies are still allowed so active conversations can continue.
Fix:
Wait for the daily limit to reset, or
Ask the agency admin to increase the daily SMS limit.
SMS Sending Suspended
SMS sending may be temporarily suspended due to high error rates, opt-outs, or carrier complaints.
Fix: Contact support to review the account status and restore sending privileges.
Phone Number and Opt-Out Issues
These failures occur after Kyrios validation but before or during carrier delivery.
Recipient Previously Opted Out
If a recipient opted out by replying STOP, SMS delivery is blocked.
Fix: The recipient must opt back in by texting START to the sending number.
Queue Overflow Errors
Queue overflow occurs when too many messages are queued at once and cannot be delivered within the allowed time window.
Kyrios queues SMS for up to four hours before marking them as failed.
Fix: Reduce send volume or shorten the validity period of queued messages.
Carrier Network Delivery Issues
These issues occur at the carrier level and are outside Kyrios control.
Unreachable Destination Handset
This error occurs when the phone is powered off, out of service, or temporarily unreachable.
Fix: Wait and retry later or confirm the recipient’s device status.
Message Blocked by Carrier
Messages may be blocked for reasons such as:
Recipient is on a Do Not Call or carrier block list
Previous opt-out activity
Toll-free number restrictions
Fix: Confirm opt-in status and ensure compliant messaging practices.
Attachment Size Too Large
SMS or MMS messages with large attachments may fail.
Fix: Reduce attachment size or send a link instead of a file.
International SMS Failures
International messages may fail due to country-level restrictions or unsupported routes.
Fix: Verify that the destination country supports SMS delivery from Kyrios.
Message Content and Length Issues
Message Exceeds Character Limits
SMS messages have a maximum length of approximately 1600 characters.
Dynamic fields such as {{message.body}} can expand unexpectedly and exceed limits.
Fix: Shorten the message or reduce dynamic content usage.
SMS Charges for Failed Messages
Charges apply when an SMS delivery attempt is made, even if the message ultimately fails.
This covers carrier routing and validation costs.
What to Do If a Valid Number Still Fails
If the number is valid but delivery continues to fail:
Check for carrier outages
Confirm opt-in status
Verify account limits and suspension status
If issues persist, contact support with the error code for investigation.