Partial SMS Delivery Disruption: Africell to Unitel Interconnect

Update timeline

1. investigating Apr 27, 2026, 12:01 PM UTC

   Status: Investigating Investigating - We are currently investigating an issue affecting SMS delivery specifically for messages originated from the Africell network destined for Unitel subscribers. Our monitoring systems indicate that while our infrastructure is healthy, there is a disruption in the interconnectivity between these two carriers. Current Service Status: • Africell ➔ Africell: Functional (OK) • Unitel ➔ Unitel: Functional (OK) • Unitel ➔ Africell: Functional (OK) • Africell ➔ Unitel: Service Disruption (Failures) Note on System Stability: Please be advised that our internal systems remain fully operational. All traffic utilizing the Unitel network to reach Unitel recipients continues to be processed and delivered without delay or interference. We are in contact with the carriers to identify the root cause and restore full connectivity. Next Update: We will provide another status update within 90 minutes. Affected components Angola - Africell Network (Partial outage)

2. investigating Apr 27, 2026, 05:08 PM UTC

   Status: Investigating Investigating – We have been actively attempting to engage with Africell's technical support team for the past several hours. However, we have yet to receive a formal acknowledgment or an Estimated Time of Restoration (ETA) regarding the interconnect link to Unitel. Our real-time monitoring confirms that the service status remains as previously reported: • Africell ➔ Unitel: Service Disruption (Messages failing to reach destination). • Unitel ➔ Unitel: Fully Operational. Our system continues to process all traffic via the Unitel network without any issues. • Africell ➔ Africell: Fully Operational. We are continuing to escalate this matter through all available carrier channels. Given the lack of feedback from the operator, we are extending our communication window to allow more time for their technical teams to respond and for our own further escalations. Next Update: We will provide our next update in 16 hours, or sooner if we receive a definitive response from the carrier. Affected components Angola - Africell Network (Partial outage)

3. monitoring Apr 28, 2026, 12:30 PM UTC

   Status: Monitoring Signs of Recovery and Backlog Processing We are observing initial signs of recovery regarding the SMS interconnectivity between Africell and Unitel. Our monitoring systems have detected that messages queued from the previous 24 hours are starting to be delivered to destination handsets. This suggests that the carrier's technical teams are working on a resolution, although we have not yet received a formal response or confirmation from Africell support. Current Routing Strategy: To ensure maximum reliability, we are keeping the direct Africell ➔ Unitel route disabledwithin the Ziett platform for the time being. • All traffic destined for Unitel subscribers will continue to be automatically routed through our dedicated Unitel ➔ Unitel path. • This ensures that your current messages are delivered instantly and are not stuck in the carrier's recovery queue. We will only reactivate the Africell-originated route once we receive official confirmation of stability from the operator and verify that the delivery success rate has normalized. Next Update: We will provide another update within 6 hours or as soon as we receive carrier feedback. Affected components Angola - Africell Network (Partial outage)

4. resolved Apr 29, 2026, 10:18 PM UTC

   Status: Resolved Service Normalized and Precautionary Measures Active Our continuous monitoring confirms that the SMS delivery flow has been normalized. Messages previously held in the carrier's queue have been successfully processed and delivered to Unitel subscribers. Although we have not yet received a formal resolution notice from Africell's technical team, our internal telemetry and delivery success rates indicate that stability has been restored. Therefore, we are marking this incident as resolved. Precautionary Measure (Next 48 Hours): To ensure the continued reliability of your communications and to guard against any potential residual instability, we have decided to keep the direct Africell ➔ Unitel route disabled for the next 48 hours as a quarantine period. • During this time, all traffic destined for Unitel subscribers will continue to be automatically routed via our direct Unitel ➔ Unitel path, which remains 100% operational. • This routing adjustment is entirely transparent and has no impact on delivery speed, features, or messaging costs. We appreciate your patience during this carrier-side disruption. Our team will continue to monitor traffic patterns closely over the coming days. Affected components Angola - Africell Network (Operational)