Issue Summary

Multiple end-users aren't receiving the voice notification from JSM Operations, and the activity log in the alert says "no-answer". This is happening for Vivo carrier.

Steps to Reproduce

1. N/A

Expected Results

The end-users using Vivo carrier should receive the voice notification call.

Actual Results

These users didn't receive the call on their phone. This is happening because on June 1st, Vivo implemented aggressive, network-wide anti-spam filtering technologies. This new mechanism automatically intercepts, blocks, or silently rejects certain inbound international traffic streams before they can be delivered to the end-user’s handset

Workaround

The end-users must contact the carrier (Vivo) or use its app to disable the anti-spam filtering for their phone number. This will make the calls being delivered to them successfully.