### Check for existing issues

- [x] I have searched the existing issues and checked that my issue is not a duplicate.

### What happened?

A bug happened! the body send to Dashscope has an redundant curly braces

<img width="668" height="754" alt="Image" src="https://github.com/user-attachments/assets/cc149672-1fa7-4e16-b66b-cba3f4f8d296" />

### Steps to Reproduce

1. Add a Dashscope Model 2. test connect

### Relevant log output

```shell litellm.BadRequestError: DashscopeException - No static resource api-openai/v1/chat/completions/chat/completions. stack trace: Traceback (most recent call last): File "/app/.venv/lib/python3.13/site-packages/litellm/llms/openai/openai.py", line 930, in acompletion headers, response = await self.make_openai_chat_completion_request( ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ ...<4 lines>... ) ^ File "/app/.venv/lib/python3.13/site-packages/litellm/litellm_core_utils/logging_utils.py", line 297, in async_wrapper result = await func(*args, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "/app/.venv/lib/python3.13/site-packages/litellm/llms/openai/openai.py", line 461, in make_openai_c…