# OneSignal: Major incident: Intermittent errors on /api/v1/notifications api

**Summary:** OneSignal reported major intermittent errors creating notifications through /api/v1/notifications, affecting some customers from 2026-09-18 00:48 UTC until resolution at 2026-09-18 01:23 UTC (34 min). Heavy load on a notification service caused the errors; OneSignal scaled up resources and confirmed the endpoint was stable for all customers. _(machine-written, sol)_
- Kind: Major incident · Label: degradation (model (Jev))
- Changed: 2026-09-18 00:48 UTC · Detected: 2026-10-17 18:22 UTC
- [Source: https://status.onesignal.com/incidents/01M2RZS4E9MXR0WS6VXWHDJ248](https://status.onesignal.com/incidents/01M2RZS4E9MXR0WS6VXWHDJ248)
- [Company: OneSignal](https://rewindex.com/company/onesignal.md)
- Versions: before (none: first archived) → after incident\_version:123/01M2RZS4E9MXR0WS6VXWHDJ248@41433a1fbc76
- Change 1 of 1 for this incident

## What changed

**1. Added: Title**

```diff
+ Intermittent errors on /api/v1/notifications api
```

**2. Added: Impact**

```diff
+ major
```

**3. Added: Status**

```diff
+ resolved
```

**4. Added: Start time**

```diff
+ 2026-09-18 00:48 UTC
```

**5. Added: Resolved time**

```diff
+ 2026-09-18 01:23 UTC
```

**6. Added: Update** (identified) · 2026-09-18 00:48 UTC

```diff
+ We have identified the root cause and are working towards a resolution. Heavy load on one of our notification services is causing intermittent errors when trying to create a notification. Not all customers are affected. The team is working on adding more capacity to the affected service. We will provide another update in 15 minutes.
```

**7. Added: Update** (identified) · 2026-09-18 01:13 UTC

```diff
+ A fix is rolling out now for the affected notifications services that are overloaded. Things should be stable within the next 10 minutes.
```

**8. Added: Update** (resolved) · 2026-09-18 01:23 UTC

```diff
+ /api/v1/notifications create endpoint is now stable for all customers. The team has scaled up resources to handle increased load on our notifications service.
```

## History of this incident

| When (UTC) | Change | Label |
| --- | --- | --- |
| 2026-09-18 00:48 UTC | Major incident: Intermittent errors on /api/v1/notifications api (this change) | degradation |

All OneSignal changes: [timeline](https://rewindex.com/company/onesignal/changes.md)
_Diff excerpts are shown on normalized text: dates, counters and tokens appear as ‹date›, ‹count›, ‹tok›; noise-only edits are hidden. Rewindex shows the changed passages, not a copy of the page._


---
Canonical: https://rewindex.com/change/i2299c82b6f4a0c · Markdown: https://rewindex.com/change/i2299c82b6f4a0c.md · JSON: https://rewindex.com/api/v1/changes/i2299c82b6f4a0c · Generated 2026-10-18T03:33:56.274Z