# unsupported_grant_type

> OAuth (Sign in with Tickwire): the token endpoint only supports authorization_code and refresh_token.

Source: https://tickwire.io/docs/errors/unsupported_grant_type/

HTTP 400.

**Likely cause:** grant_type is password, client_credentials, implicit or another type.

**What to do:** Use the authorization code flow with PKCE.

**Retry:** No. The same request gets the same answer; change something first.

Listed under [Sign in with Tickwire (OAuth)](https://tickwire.io/docs/errors/#sign-in-with-tickwire-oauth) in [Errors](https://tickwire.io/docs/errors/). Send the error's `requestId` to support and we can find the request.