error with Datasets.add_files_to_dataset()

[Scott771]

from indico_toolkit.pipelines import FileProcessing
from indico_toolkit.indico_wrapper import Datasets

dsets = Datasets(client, dataset_id=122)
fp = FileProcessing()
fp.get_file_paths_from_dir("./metlife_fin_loans/bank_notices_extra_data/",recursive_search=True)
dsets.add_files_to_dataset(fp.file_paths)

Error:
`IndicoRequestError Traceback (most recent call last)
in
----> 1 dsets.add_files_to_dataset(fp.file_paths)

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico_toolkit/indico_wrapper/dataset.py in add_files_to_dataset(self, filepaths)
48
49 def add_files_to_dataset(self, filepaths: List[str]) -> Dataset:
---> 50 dataset = self._upload_files(filepaths)
51 return self._process_uploaded_files(dataset)
52

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico_toolkit/indico_wrapper/dataset.py in _upload_files(self, filepaths)
105
106 def _upload_files(self, filepaths):
--> 107 return self.client.call(AddFiles(dataset_id=self.dataset_id, files=filepaths))

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico/client/client.py in call(self, request)
62
63 if isinstance(request, RequestChain):
---> 64 return self._handle_request_chain(request)
65 elif request and isinstance(request, HTTPRequest):
66 return self._http.execute_request(request)

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico/client/client.py in _handle_request_chain(self, chain)
37 for request in chain.requests():
38 if isinstance(request, HTTPRequest):
---> 39 response = self._http.execute_request(request)
40 chain.previous = response
41 elif isinstance(request, RequestChain):

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico/http/client.py in execute_request(self, request)
76 return request.process_response(
77 self._make_request(
---> 78 method=request.method.value.lower(), path=request.path, **request.kwargs
79 )
80 )

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico/queries/datasets.py in process_response(self, response)
328
329 def process_response(self, response):
--> 330 return Dataset(**super().process_response(response)["addDatasetFiles"])
331
332

~/Desktop/jupyter_kernels/new_client/venv/lib/python3.7/site-packages/indico/client/request.py in process_response(self, response)
43 error="\n".join(error["message"] for error in errors),
44 code=400,
---> 45 extras=extras,
46 )
47 return response["data"]

IndicoRequestError: Status: 400, Error: Variable "$metadata" got invalid value "null".
Expected type "JSONString", found "null".
Extras: {'locations': [[{'column': 41, 'line': 2}]]}`