Reasons behind a failed SMS

MSG91 Error Codes

 (These are visible on MSG91 logs and reports)

Simplified Description

(For better understanding)

Absent Subscriber

The handset is switched off or in a low/no signal area

Alpha Header not allowed on Promo-Numeric Route

Alphanumeric Sender ID not allowed on promo numeric route

Blackout Time

SMS sent during restricted time window

Call Barred

The Telecom operator has placed a restriction on the SIM card that prevents you from receiving (incoming) SMSs.

DND Failure

SMS blocked due to DND rules

Destination Flooding

Too many SMSs sent to the same number

Duplicate SMS within a Time Zone

The same SMS is sent multiple times within a restricted time

Equipment Protocol Error

The recipient's device (handset) or network couldn't properly process a SMS due to a temporary incompatibility or network issue

Globally Blacklist Number / Sender Id

The number or Sender ID is globally blacklisted

Invalid Number

Number is not in proper format (91XXXXXXXXXX)

Memory Capacity Exceeded

Handset SMS inbox capacity is full

Message Multipart not complete

One or more parts of the multipart SMS failed

Message Not Submitted (Timeout)

SMS could not be submitted due to the telecom operator’s system timeout

Message Service not Supported

Handset has no active SMS service/recharge

Message Validity Expired

Handset was off/out of coverage; SMS expired

Multiple Submissions on Same Number

Repeated submissions to the same number in a short duration

Network Congestion

A telecom operator performance issue where a network gets overloaded with more traffic than it can handle

Network Issue

A temporary problem in the telecom network. This may be caused by signal issues or operator-side disruptions.

Resource Unavailable

The required network resource was not available

Roaming not allowed

The subscriber is in an unsupported roaming area

Spam Failure

SMS flagged as spam

Subscriber Busy

The subscriber’s phone was busy and couldn’t receive the SMS. This often happens if they are on a call on another SIM.

Teleservice not Supported

The telecom operator had suspended the subscriber’s mobile services. As a result, the number is not eligible to receive SMS.

The remote address not reachable

The destination address is invalid, or the recipient’s handset is currently unreachable due to poor or no network connectivity.

TimeOut

SMS cancelled after the cut-off time

Unknown Subscriber

The destination mobile number is not recognized by the telecom operator. This usually occurs when the number is invalid, disconnected, or not active on the operator’s network.

MSG91 Error Codes

 (These are visible on MSG91 logs and reports)

Simplified Description

(For better understanding)

Blocked by DLT

SMS blocked due to DLT compliance rules

Callback Number not Whitelisted on DLT under CTA

The callback number is not approved under CTA on DLT

CTA not Whitelisted on DLT

CTA is not approved/whitelisted on DLT

DLT Consent Error

Issue related to user consent on DLT

DLT Entity ID failure

Failure during Entity ID validation

DLT Entity Id Blank

Entity ID is missing in the request

DLT Entity Id Error

Incorrect Entity ID provided

DLT Entity Id not matched with Header (Sender Id) on DLT

Entity ID does not match the registered Sender ID

DLT Header (Sender Id) Error

Issue with the registered Sender ID

DLT Related Failure

Generic DLT-related failure

DLT Scrubbing Failed

SMS failed DLT content scrubbing

Telemarketer not Registered on DLT

The telemarketer is not registered on DLT

Telemarketer ID does not Exist / is Inactive on DLT

Telemarketer ID is missing or inactive on DLT

Telemarketer Blacklisted on DLT

The telemarketer is blacklisted on DLT

Template/Header Blacklisted on DLT

The template or header is blacklisted on DLT

DND: Content is Promo and Preference Status not matched on DLT

SMS blocked due to promotional content and user preference on DLT

DLT Template Error

Issue with the registered DLT template

DLT Template variable exceeded max length

Variable exceeds 40-character limit

DND: Failed as Preferred Day is Blocked

SMS sent on a blocked day as per user preference

DND: Failed as Preferred Time is Blocked

SMS sent outside the allowed time window

DND: Failed due to Preference Category

SMS category not allowed by user preference

DND: Fully Blocked or Promo Blocked

Number is fully blocked for promotional SMS

DND: Preference Status is Active

User has active DND preference

Email not Whitelisted on DLT under CTA

Email ID is not approved under CTA on DLT

Entity Blacklisted on DLT

Entity is blacklisted on DLT platform

Entity Inactive on DLT

Entity is not active on DLT

Entity not Registered on DLT

Entity is not registered on DLT

Entity not found on DLT

Entity ID does not exist on DLT

Error Identifying Template

Unable to identify correct template

Header (Sender Id) Blacklisted on DLT

Sender ID is blacklisted on DLT

Header (Sender Id) Inactive on DLT

Sender ID is inactive on DLT

Header (Sender Id) not Found on DLT

Sender ID is not registered on DLT

Header (Sender Id) not registered for Template on DLT

Sender ID is not mapped to template

Header not Associated with this Template

Sender ID is not linked to this template

Header Suspended due to Customer on DLT

Sender ID suspended based on customer request/action

Header Suspended due to Usage on DLT

Sender ID suspended due to usage-related issues

Header Suspended due to Validity on DLT

Sender ID suspended because its validity expired

Invalid DLT Entity Id

Incorrect or invalid Entity ID format

Invalid Template Id

The template ID provided is incorrect

Invalid SMS Timing on DLT

SMS sent outside allowed timing as per DLT

PE-TM Chain Error on DLT

Error in Principal Entity–Template Chain on DLT

PE-TM Chain PE ID not matched on DLT

Entity ID does not match in the PE-TM chain

PE-TM Chain Suspended | Blacklisted on DLT

PE-TM chain is suspended or blacklisted

PE-TM Chain TM ID not matched on DLT

Template ID does not match in PE-TM chain

PE-TM Chain not Registered on DLT

The PE-TM chain is not registered on DLT

Preference not Matched on DLT

SMS does not match the user's preference

Sender ID (Header) blocked on DLT

Sender ID blocked on DLT

Template Blacklisted on DLT

Template is blacklisted on DLT

Template ID not found on DLT

Template ID does not exist on DLT

Template Id Missing

Template ID not provided

Template Inactive on DLT

The template is inactive on DLT

Template Suspended due to Customer on DLT

Template suspended based on customer request/action

Template Suspended due to Usage on DLT

Template suspended due to usage-related issues

Template Suspended due to Validity on DLT

Template suspended because its validity expired

Template not found on DLT

Template does not exist on DLT

Template not matched on DLT

SMS content does not match the template

URL Blacklisted on DLT under CTA

CTA URL is blacklisted on DLT

URL Inactive on DLT under CTA

CTA URL is inactive on DLT

URL not Found on DLT under CTA

CTA URL is not registered on DLT