Authenticate | Negative balance | Check your AI Center- Billing. See if the balance in Hybrid Wallet Balance is negative. | Replenish the wallet to put it in positive balance. System reconfiguration will take effect within 10-15mins. |
21211 | Invalid “To” phone number | Recipient number is invalid, incorrectly formatted, or not a valid destination. | Correct the recipient number and use E.164 format: +[country code][number]. |
21408 | Messaging not allowed to destination region | The destination country or region is not enabled or is unsupported. | Confirm the destination is supported. Contact Support when messaging to the region should be available. |
21606 | Invalid or unavailable “From” number | Sender capability, ownership, formatting, porting/hosting status, or country restrictions. | Use an active SMS-capable number owned by the sub-account and confirm it is fully provisioned. |
21610 | Recipient unsubscribed or SMS DND is enforced | Whether the contact replied STOP, used another opt-out keyword, or has applicable DND enabled. | Do not continue sending. The recipient must validly opt back in, such as by sending START or another supported opt-in keyword. |
21612 | Current “To” and “From” combination cannot be used | E.164 formatting, destination-country restrictions, sender type, and route availability. | Correct number formatting or use a supported/local sender for the destination. Contact Support if the route should be supported. |
21614 | “To” number is not a valid mobile number | The destination may be invalid, incorrectly formatted, or a landline. | Verify the number is a valid mobile number and is formatted correctly. |
21635 | Destination is a landline | The recipient number was identified as a landline that cannot receive SMS. | Use another SMS-capable number for the contact. Contact Support if the number is known to be mobile. |
21661 | Sending number is not SMS-capable | Capabilities of the selected HighLevel phone number. | Select or purchase a phone number that supports SMS. |
30002 | Account suspended before message delivery | Account or sub-account suspension caused by balance or policy concerns. | Contact HighLevel Support. Do not direct LC Phone users to an external provider for this error. |
30003 | Number unreachable or out of service | Device power/signal, mobile capability, recipient carrier, or recurring carrier filtering. | Verify the number and retry later when appropriate. For repeated failures, collect at least 3 recent examples and contact Support. |
30004 | Destination blocked or unavailable | DND/opt-out status, destination signal, landline status, carrier issues, or regional DNC requirements. | Check the contact's SMS DND status and destination. If the error persists across valid recipients, collect 3 recent examples for Support. |
30005 | Recipient number inactive or does not exist | Correct phone number, E.164 formatting, active service, and mobile capability. | Correct or remove invalid destinations. If a known-valid number repeatedly fails, collect recent examples for Support. |
30006 | Landline or unreachable carrier | Whether the destination can receive SMS through the selected phone-number type. | Use a valid mobile destination or another supported route. |
30007 | Message filtered | Content, sender identification, consent, URLs, prohibited content, spam signals, and carrier rules. | Correct the underlying compliance/content issue before resending. If compliant traffic continues to fail, collect 3+ affected examples and contact Support. 30007 guide. |
30008 | Unknown delivery error | Message length, character encoding, content, and whether the issue affects multiple recipients. | Test a shorter, simple message. If the failure continues, provide Support with 3+ recent affected messages. |
30011 | MMS unsupported by destination or region | Recipient device MMS capability and regional MMS availability. | Send text-only SMS when MMS is unavailable, or use another supported destination/channel. |
30023 | Daily message cap reached | Current A2P brand messaging volume and whether the daily carrier cap has been reached. | Pause additional sending and contact Support if the limit is unexpected or requires investigation. |
30024 | Numeric Sender ID not provisioned | Whether the destination country requires sender registration and whether provisioning has completed. | If the sender should already be registered, collect at least 3 Message IDs showing Error 30024 and contact Support. |
30032 | Toll-Free number is not verified | Toll-Free Verification status for the sending number. | Complete Toll-Free Verification and wait for Verified (Approved) status before sending. |
30033 | A2P 10DLC campaign suspended | Campaign status and any compliance or registration issue associated with the campaign. | Contact Support to review the suspension reason and required recovery steps. |
30034 | Number not fully registered for A2P messaging | Approved campaign, number-to-campaign association, carrier activation period, and Sole Proprietor limitations. | Confirm the number is linked to the approved campaign. Allow up to 24 hours after approval for carrier activation. Sole Proprietor registrations support one local number per campaign. 30034 guide. |
30037 | Outbound messaging disabled | Whether outbound messaging has been disabled at the account level. | Contact Support if |
Only one contact fails | Check the recipient number, SMS DND/opt-out status, number type, and exact error code. |
Several contacts on one carrier fail | Check for filtering, destination-carrier issues, and repeated 30003/30007 patterns. |
All local-number SMS suddenly fails | Check A2P campaign status, number association, account restrictions, and errors such as 30033, 30034, or 30037. |
All Toll-Free SMS fails | Check Toll-Free Verification status and Error 30032. |
Only MMS fails | Check attachment size/type, destination MMS capability, and Errors 11751 or 30011. |
Workflow SMS fails but manual SMS works | Review the workflow execution, sending number, contact DND state, and message content at the exact time the action ran. |