Phone System Error Codes and Warnings

This article provides a comprehensive list of error codes and warnings you may encounter while using the Enrollio phone system. Each code includes clear explanations, common causes, and solutions to help you resolve delivery issues quickly and keep your communications with families running smoothly.

What Are Phone System Error Codes?

Enrollio's phone system generates specific error codes when messaging or calling actions fail. These codes help identify the root cause of delivery issues. By understanding this dictionary, you can diagnose problems accurately and maintain effective communication with prospective families and current parents.

Below is a complete list of error codes along with their meanings, common causes, and actionable solutions.

21211: Invalid 'To' Phone Number

You attempted to send a message or make a call, but the phone number you supplied was invalid or incorrectly formatted.

Enrollio accepts phone numbers in E.164 format: [+] [country code] [subscriber number including area code]

Common Causes

  • The number formatting was invalid
  • You attempted to send from an Enrollio number to itself
  • You attempted to send a message to a Short Code
  • You attempted to send a message to an Alphanumeric Sender ID
  • The number has an invalid prefix

How to Fix It

  1. Format your phone numbers in E.164 format: [+] [country code] [subscriber number including area code]
  2. Verify you're using the correct country calling code
  3. Don't attempt to call or message from an Enrollio number to itself
  4. Review the number for typos or incorrect input
  5. Remove invalid prefixes and send directly to the number in E.164 format

21408: Your Account Cannot Send SMS to This Country or Region

You attempted to send a message to a region that hasn't been enabled in your account. These settings help ensure you only send messages to countries or regions where you operate.

Common Causes

  • The destination country or region is not enabled in your account settings
  • You attempted to send to a region not supported by Enrollio (such as Iran, which includes all numbers beginning with +98)

How to Fix It

Contact Enrollio Support to enable messaging for your desired region.

Note: To align with regulatory requirements, Enrollio has stopped delivering voice and messaging traffic to recipients in Iran starting March 15, 2025.

21614: 'To' Number Is Not a Valid Mobile Number

You attempted to send a text message to a number that isn't a valid mobile number. The number is likely a landline or invalid.

Common Causes

  • The number is a landline
  • The number is invalid or formatted incorrectly
  • The number uses a non-standard format (such as IoT or machine-to-machine numbers)

How to Fix It

  1. Confirm the number is not a landline
  2. Verify you've provided a valid mobile number in proper E.164 format
  3. If sending to an IoT or M2M number, contact Support for assistance with non-standard formats

21635: The "To" Number Is a Landline and Cannot Receive SMS

You attempted to send a text message to a landline number, which cannot receive SMS.

How to Fix It

Verify the number with the parent or family member. If you're certain it's not a landline, contact Enrollio Support.

21661: 'From' Number Is Not SMS-Capable

The phone number you're using to send messages is not capable of sending text messages.

Common Cause

The number you're using doesn't have SMS capabilities enabled.

How to Fix It

  1. Click Settings > Phone Numbers > Manage Number
  2. Verify your current number has SMS capabilities
  3. If not, purchase an SMS-capable number by clicking +Add Number
[SCREENSHOT: Settings > Phone Numbers > Manage Number screen showing SMS capabilities column]

30002: Message Failed - Account Currently Suspended

Your message failed because your account was suspended after the message was queued but before it was sent.

Common Causes

  • Account was suspended for lack of funds after your message was queued
  • Account was suspended due to a violation of our Acceptable Use Policy

How to Fix It

Contact Enrollio Support immediately to resolve the suspension.

30003: Number Unreachable or Out of Service

The phone you're trying to reach is switched off or otherwise unavailable.

Common Causes

  • The recipient's phone is switched off
  • The recipient is in an area with no cellular coverage
  • The number is no longer in service

How to Fix It

Wait and try sending your message again later. If the issue persists, verify the phone number with the parent or family member.

30004: Recipient Has Opted Out or Has DND Enabled

The recipient has opted out of receiving messages from your center or has Do Not Disturb (DND) enabled.

How to Fix It

  1. Check the parent or family's record to see if they've opted out
  2. Respect their preferences — don't attempt to message them again unless they opt back in
  3. Reach out through an alternative method (email or phone call) if necessary
Pro Tip: Always maintain clean opt-out lists to stay compliant with messaging regulations and maintain trust with families.

30005: Recipient's Number Is Inactive or Does Not Exist

The phone number you're trying to reach is inactive or doesn't exist.

How to Fix It

Verify the phone number with the parent or family member and update your records.

30006: Landline or Unreachable Carrier

You attempted to send a text message to a landline, or the recipient's carrier is unreachable.

How to Fix It

  1. Verify the number is a mobile phone number
  2. If the carrier is temporarily unreachable, try again later
  3. Update your records with the correct mobile number if needed

30007: Message Filtered

Your message was filtered by the recipient's carrier. This typically happens when carriers detect spam-like content or suspicious messaging patterns.

How to Fix It

  1. Review your message content for spam triggers (excessive caps, too many links, etc.)
  2. Ensure your messaging practices comply with carrier guidelines
  3. Contact Support if you believe your message was incorrectly filtered

30008: Unknown Error

An unknown error occurred while attempting to deliver your message.

How to Fix It

  1. Try sending your message again
  2. If the error persists, contact Enrollio Support with the error details

30011: MMS Not Supported by Receiving Phone Number

You attempted to send an MMS (picture message) to a phone number that doesn't support MMS in that region.

How to Fix It

Send a text-only message instead, or verify the recipient's phone supports MMS.

30023: Daily Message Cap Reached

You've reached your daily message sending limit.

How to Fix It

  1. Wait until tomorrow to send additional messages
  2. Contact Enrollio Support if you need to increase your daily message cap

30032: Toll-Free Number Has Not Been Verified

You're attempting to send messages from a toll-free number that hasn't been verified yet.

How to Fix It

  1. Complete the toll-free number verification process
  2. Use a verified local number in the meantime
  3. Contact Support if you need assistance with verification

21610: Attempt to Send to Unsubscribed Recipient

You attempted to send a message to a parent or family member who has unsubscribed from your messages.

How to Fix It

  1. Respect the unsubscribe request and remove the number from your messaging lists
  2. Use an alternative communication method if you need to reach them

30033: US A2P 10DLC Campaign Suspended

Your A2P (Application-to-Person) 10DLC messaging campaign has been suspended.

Common Causes

  • Compliance violations
  • Excessive spam complaints
  • Incomplete or inaccurate campaign registration

How to Fix It

Contact Enrollio Support immediately to resolve the suspension and restore your messaging capabilities.

30037: Outbound Messaging Disabled

Outbound messaging has been disabled for your account or phone number.

How to Fix It

Contact Enrollio Support to re-enable outbound messaging.

21612: Message Cannot Be Sent with Current "To" and "From" Parameters

The combination of your sending number and destination number is not allowed.

Common Causes

  • Regulatory restrictions between certain number types or regions
  • Carrier restrictions
  • Account configuration issues

How to Fix It

  1. Try using a different sending number if you have multiple numbers
  2. Verify the destination number is correct and formatted properly
  3. Contact Support if the issue persists

30034: Number Not Fully Registered for A2P Messaging

Your number has been approved for A2P messaging but isn't fully registered yet.

How to Fix It

Wait up to 24 hours after approval for registration to complete. If it's been longer than 24 hours, contact Enrollio Support.

21606: The 'From' Phone Number Is Not Valid for This Destination

The phone number you're using to send messages is not valid or capable of sending messages to this specific destination.

How to Fix It

  1. Verify your sending number is message-capable
  2. Check if there are regional restrictions for the destination
  3. Try using a different sending number if available
  4. Contact Support if you need assistance
Need Help? If you continue experiencing issues after trying these solutions, contact Enrollio Support with the specific error code and details about what you were trying to do.