INFO:     192.168.97.1:53630 - "GET /ui/backfills?limit=50&offset=0&dag_id=test_api_dag HTTP/1.1" 500 Internal Server Error
ERROR:    Exception in ASGI application
Traceback (most recent call last):
  File "/usr/python/lib/python3.11/site-packages/uvicorn/protocols/http/httptools_impl.py", line 416, in run_asgi
    result = await app(  # type: ignore[func-returns-value]
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/python/lib/python3.11/site-packages/fastapi/applications.py", line 1160, in __call__
    await super().__call__(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/applications.py", line 107, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/errors.py", line 186, in __call__
    raise exc
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/errors.py", line 164, in __call__
    await self.app(scope, receive, _send)
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/gzip.py", line 29, in __call__
    await responder(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/gzip.py", line 130, in __call__
    await super().__call__(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/gzip.py", line 46, in __call__
    await self.app(scope, receive, self.send_with_compression)
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/base.py", line 191, in __call__
    with recv_stream, send_stream, collapse_excgroups():
  File "/usr/python/lib/python3.11/contextlib.py", line 158, in __exit__
    self.gen.throw(typ, value, traceback)
  File "/usr/python/lib/python3.11/site-packages/starlette/_utils.py", line 87, in collapse_excgroups
    raise exc
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/base.py", line 193, in __call__
    response = await self.dispatch_func(request, call_next)
               ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/airflow/airflow-core/src/airflow/api_fastapi/auth/middlewares/refresh_token.py", line 61, in dispatch
    response = await call_next(request)
               ^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/base.py", line 168, in call_next
    raise app_exc from app_exc.__cause__ or app_exc.__context__
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/base.py", line 144, in coro
    await self.app(scope, receive_or_disconnect, send_no_error)
  File "/usr/python/lib/python3.11/site-packages/starlette/middleware/exceptions.py", line 63, in __call__
    await wrap_app_handling_exceptions(self.app, conn)(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/_exception_handler.py", line 53, in wrapped_app
    raise exc
  File "/usr/python/lib/python3.11/site-packages/starlette/_exception_handler.py", line 42, in wrapped_app
    await app(scope, receive, sender)
  File "/usr/python/lib/python3.11/site-packages/fastapi/middleware/asyncexitstack.py", line 18, in __call__
    await self.app(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/routing.py", line 716, in __call__
    await self.middleware_stack(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/routing.py", line 736, in app
    await route.handle(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/routing.py", line 290, in handle
    await self.app(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/fastapi/routing.py", line 130, in app
await wrap_app_handling_exceptions(app, request)(scope, receive, send)
  File "/usr/python/lib/python3.11/site-packages/starlette/_exception_handler.py", line 53, in wrapped_app
    raise exc
  File "/usr/python/lib/python3.11/site-packages/starlette/_exception_handler.py", line 42, in wrapped_app
    await app(scope, receive, sender)
  File "/usr/python/lib/python3.11/site-packages/fastapi/routing.py", line 116, in app
    response = await f(request)
               ^^^^^^^^^^^^^^^^
  File "/usr/python/lib/python3.11/site-packages/fastapi/routing.py", line 691, in app
    content = await serialize_response(
              ^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/python/lib/python3.11/site-packages/fastapi/routing.py", line 302, in serialize_response
    return serializer(
           ^^^^^^^^^^^
  File "/usr/python/lib/python3.11/site-packages/fastapi/_compat/v2.py", line 218, in serialize_json
    return self._type_adapter.dump_json(
           ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/usr/python/lib/python3.11/site-packages/pydantic/type_adapter.py", line 672, in dump_json
    return self.serializer.to_json(
           ^^^^^^^^^^^^^^^^^^^^^^^^
pydantic_core._pydantic_core.PydanticSerializationError: Error serializing to JSON: ValidationError: 1 validation error for ValidatorIterator
1.dag_run_conf
  Input should be a valid dictionary [type=dict_type, input_value=None, input_type=NoneType]