# Project Type Not Supported
source: https://developer.mastercard.com/mastercard-developers-api/documentation/errors/project-type-not-supported/index.md

Authentication type defined in the request is not supported for your project. For example, you can encounter this error if your project supports `OAUTH10A` but you add `MTLS` in your request.

### Solution {#solution}

Ensure you are using the authentication type that is supported by your project.

### API Error Response {#api-error-response}

**HTTP code 400**

```JSON
{
  "Errors": {
    "Error": [
      {
        "Source": "DEVELOPERS_API",
        "ReasonCode": "PROJECT_TYPE_NOT_SUPPORTED",
        "Description": "Project type not supported",
        "Details": "1662389676788-7e6e4701-8434-47ae-a181-26cfa8f89c01",
        "Recoverable": false

      }
    ]
  }
}
```

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