---
title: "E02098 — MTLSLastCertificateAuthority"
description: "The last certificate authority cannot be removed while the mTLS state is evaluating or enforced."
canonical: "https://bird.com/docs/api/errors/E02098"
---

# E02098 — MTLSLastCertificateAuthority

The last certificate authority cannot be removed while the mTLS state is evaluating or enforced.

- **HTTP status**: `409`
- **Type**: `conflict_error`
- **Name**: `MTLSLastCertificateAuthority`

## What to do

Add the replacement certificate authority first, or set the mTLS state to disabled, then remove this one.

## Related

- [Idempotency](/docs/api/idempotency): safe retries and key reuse rules
- [E02xxx — Auth & identity](/docs/api/errors/E02xxx): every code in this range
- [Errors](/docs/api/errors): the full wire contract, status mapping, and error catalog
- [Error handling](/docs/guides/errors): branching on `type` and `code`, validation details, and `vendor_code`

## Related resources

- [Should I use a Bird SDK or call the API directly?](/explained/platform/should-i-use-an-sdk-or-call-the-api-directly) (answer)
- [Build your first integration](/learn/paths/integration) (course)
- [Send your first email](/docs/get-started/send-your-first-email) (docs)

[Get an implementation brief](/learn/workspace?topic=api-basics)