Symantec VIP: Reporting on SMS Blocks Triggered by Unusual Traffic

Products

• VIP Service

Issue/Introduction

You may experience a sudden block on SMS authentication codes to specific countries due to automated fraud prevention triggers. This occurs when an unusual spike in SMS traffic is detected. Affected users may be unable to receive OTPs during these periods.

Symptoms

• Users in a specific region or country stop receiving SMS security codes.
• The "SMS Block" is triggered by Symantec's infrastructure to prevent fraudulent activity.
• Individual phone numbers in the affected region may be blocked specifically.

Environment

• Symantec VIP Service
• VIP Manager Portal

Cause

A significant surge in SMS delivery requests to a specific country (e.g., Australia) triggers an automated security threshold within the Symantec VIP/Twilio delivery infrastructure. This is a protective measure to mitigate potential SMS toll fraud or phishing campaigns.

Resolution

To check the daily SMS Messages limit, Login to VIP manager and then follow the arrows provided in the screen shot to check the limit per country.

 

To run the report for SMS/Voice consumption by month, follow the arrows provided in the screen shot.

Errors see been users when the SMS Limit has been reached for a specific area code, see below: