SIP Trunk Service Disruption

Incident Report for Teamtel

Postmortem

Title: Incoming calls unavailable (resolved)

Status: Resolved
Severity: Major outage
Affected service: Telephony, incoming calls
Period: 22 October 2026, 20:00 to 23 October 2026, 09:08

Resolved (23 October 2026, 09:08)
Our carrier rolled back the change. Since 09:08, incoming calls are coming in normally again. We have confirmed that the service is running stably.

What happened?
On 22 October at 20:00, our carrier made a planned change to its number routing. A fault in the number conversion caused incoming calls to some numbers to be rejected. Callers got an error message or a busy tone and could not get through.

What measures are being taken?

The number conversion is being corrected and will be tested thoroughly before it goes live.
After every routing change, incoming calls will be checked right away to make sure they arrive correctly.
Monitoring and alerts are being added for rejected incoming calls, so an outage is spotted faster.
Every change plan will include a fixed step for rolling the change back.

We apologise for the inconvenience. If you still have problems with incoming calls, please contact support@teamtel.be.

Posted Oct 30, 2026 - 16:21 CET

Resolved

Following adjustments made at 09:05, services have now been restored and inbound calling is operating normally again.

Our investigation has confirmed that the issue was not related to our datacentre infrastructure. The disruption was isolated to the SIP trunk service, resulting in a subset of customers experiencing issues with inbound calls. Outbound calling was not affected.

Internal calls between extensions have also been fully restored.

We are engaging with our provider to conduct a further investigation into the root cause. At this stage, all indications point towards a routing-related issue within the SIP trunk path.

We will continue to monitor the service closely, but all systems are currently operating as expected.

We apologise for the inconvenience caused and thank customers for their patience.

Posted Oct 23, 2026 - 09:30 CEST

Investigating

We are currently experiencing issues with our SIP trunk service. Customers may encounter failed or dropped calls, one-way audio, or be unable to make or receive external calls.

Our engineers are actively investigating the cause and working to restore full service as quickly as possible. Internal calls between extensions are not affected.

We will post an update as soon as we have more information. We apologise for the inconvenience and thank you for your patience.

Posted Oct 23, 2026 - 08:18 CEST

This incident affected: Fixed Telephony (SIP Trunking).