Azure AI Foundry Agent Service Deep Research Tool Error

I have been trying to use the new deep research tool from the preview from the sample code:
[https://github.com/Azure/azure-sdk-for-python/blob/main/sdk/ai/azure-ai-agents/samples/agents_tools/sample_agents_deep_research.py](url).

I have already been granted access to the o3-deep-research model from the azure foundry.

I have also installed the prereleased version of azure-ai-projects using:
pip install --pre azure-ai-projects

And I have saved all the required environment variables in .env

However, when I run the sample code, I get the following error:

```
azure.core.exceptions.HttpResponseError: (unsupported_tool) The requested tool 'deep_research' is not supported.
Code: unsupported_tool
Message: The requested tool 'deep_research' is not supported.
```