Initiate the rotation of an M2M client secret. After this endpoint is called, both the client's `client_secret` and `next_client_secret` will be valid. To complete the secret rotation flow, update all usages of `client_secret` to `next_client_secret` and call the [Rotate Secret Endpoint](https://stytch.com/docs/b2b/api/m2m-rotate-secret)[Rotate Secret Endpoint](https://stytch.com/docs/api/m2m-rotate-secret) to complete the flow.Secret rotation can be cancelled using the [Rotate Cancel Endpoint](https://stytch.com/docs/b2b/api/m2m-rotate-secret-cancel)[Rotate Cancel Endpoint](https://stytch.com/docs/api/m2m-rotate-secret-cancel). **Important:** This is the only time you will be able to view the generated `next_client_secret` in the API response. Stytch stores a hash of the `next_client_secret` and cannot recover the value if lost. Be sure to persist the `next_client_secret` in a secure location. If the `next_client_secret` is lost, you will need to trigger a secret rotation flow to receive another one.