DLT Error Codes 611, 613, 614, 635 Explained

1. Where these codes come from

Every commercial SMS carries an entity (PE) ID, a telemarketer chain, a header and a template ID. Before delivery, the operator's scrubbing engine checks each one against the DLT ledger, then compares the text with the template and applies the recipient's preferences. A code is returned at the first check that fails.

The codes are defined by each platform, not by TRAI, and aggregators often re-label them. Infobip, for example, reports a too-long variable as error 4131. The tables below come from the response-code maps in Airtel's DLT portal. That portal holds Airtel's own table plus a second one labelled for Tanla, whose platform runs the Vi and BSNL DLT portals.

2. Airtel scrubbing codes

For 803, Airtel's tool explains: "The header you are using is either blacklisted or Inactive or Freepooled in DLT." Freepooled means returned to the header pool after inactivity; Vi and BSNL do this after 90 days without use. For blocked or inactive headers and templates, Airtel points to telemarketer.helpline@airtel.com. Header lifecycle rules are in our SMS header guide.

3. Vi and BSNL: the 600 series

The second table in Airtel's portal is labelled for Tanla, whose Trubloq platform runs the Vi and BSNL DLT portals. Neither Vi nor BSNL publishes its own code list, so treat this as the best available reference rather than their official statement. Unlisted numbers inside each range are marked "reserved".

4. "Template ID not found" (613, 630, 637)

Airtel's tool gives three explanations for 613:

• "The templateid you are passing in the request is not registered on DLT."
• "You are passing blank Template Id."
• "Invalid template id passed because at the time of scrubbing operation the template was not located in blockchain system. This can happen when the template created by entity is registered but not approved from TSP."

In practice: copy the ID from the portal as text (a spreadsheet will round a 19-digit number), confirm the status is Approved and Active, and check the template sits under the same entity as the header. If the template was approved only minutes before the send, Airtel's tool can report that the "scrubbing engine autohealed the discrepancy. Please retry now". That is the one case where a retry is right. Template rules are covered in our template registration guide.

5. "Invalid DLT entity ID" (611, 600–605, 801–802)

When the header belongs to someone else, Airtel's tool says: "The Header you are providing is not registered with entityid … that you are passing in request, please provide the correct combination". The common causes:

• Wrong or mangled ID. A typo, an ID from another account, or a number truncated by a spreadsheet.
• Header owned by another entity. Typical with group companies, or headers registered by a previous vendor (611 on Airtel, 623 in the 600 series).
• Entity inactive. Renewal unpaid or expired (802, 602). Jio disables DLT services on non-payment, and Vi gives a 30-day grace period after its one-year validity.
• Entity blacklisted (801, 603).
• Gateway not in your PE–TM chain (605). Since 11 December 2024, TRAI has had traffic on undeclared chains rejected.

Where to find the right ID and how chains work: DLT entity ID guide.

6. Content mismatch: 666 and 633

The scrubber found the template, but the text does not fit it. The usual causes:

• Fixed text edited: a word, a double space, a full stop, or a trailing line break
• A value of the wrong type for its tag, such as letters in a number variable
• A link or number in a variable that is not whitelisted, or a link inside a text variable
• Tamil or Hindi text sent against an English template
• A value over its length limit, which Airtel reports separately as 635

Since TRAI's tagging direction of November 2025, type and whitelist failures count as content failures too. Our variable tagging guide has the limits per tag and a PHP pre-check.

7. Troubleshooting order

Work from the outside in, in the same order the scrubber checks:

1. Platform. Airtel table or 600 series? The same number can mean different things.
2. Entity. Is the PE ID correct, active and renewed? Codes 611, 600–604, 801, 802.
3. Chain. Is your gateway's telemarketer bound to your PE? Codes 605, 677–680, 610–612 in the 600 series.
4. Header. Registered, active, owned by this PE, not freepooled? Codes 612, 620–623, 803, 804.
5. Template. Approved, active, linked to this header, and in a category that matches the header type? Codes 613, 614, 630–637, 683, 687, 805.
6. Content. Character-for-character match, values within tag rules, links whitelisted? Codes 666, 633, 635.
7. Recipient. DND, preferences, promotional timing or consent? Codes 201, 650–652, 660. These are not registration faults; the category may simply be wrong. See transactional vs promotional SMS.

8. How errors appear in the AvanceZone API

There are two stages, and they report differently. First, before a message leaves our gateway, it is normally matched against the templates approved on your account. If it fails, nothing is sent, and the v2 API answers with HTTP 422:

{
  "success": false,
  "error": "Template Verification Failed",
  "message": "Template verification failed: Message does not match any approved template. ...",
  "error_code": "TEMPLATE_MISMATCH",
  "details": {
    "sender_id": "AVNZON",
    "message_preview": "Your OTP for login is 482913. It is valid for 10 m...",
    "suggestion": "Please use an approved template or request template approval"
  }
}

The message field says which check failed, for example "No approved template found for sender ID…", a closest-match suggestion with a similarity score, or "Matched template … is not active". A header that is not approved on your account returns HTTP 400 "Invalid sender ID" instead. None of these are operator codes.

Second, once a message passes our check and is handed on, the API has already returned HTTP 200 with queued. If the operator's scrubber then rejects it with a code from the tables above, the message ends with status failed. The v2 API does not translate operator codes into its own error codes, so send support the message_id and we will look up the operator's reason. Code for both stages is in our PHP SMS guide.

Related DLT guides

• DLT registration for bulk SMS: the full registration path
• Portal-specific help: Airtel, Jio, Vi, BSNL