413 error in creating feature-group in AWS Feature Store

Question

This page says the number of feature_definitions can be 2500 per feature group. Also I followed all the constraints including feature_definition constraint of length of names less than 64. When creating a feature group with 2100 features via the following API:

feature_group.create(
  record_identifier_name = record_identifier_name,
  event_time_feature_name = event_time_feature_name,
  role_arn = role,
  enable_online_store = True,
  s3_uri = offline_feature_store_bucket
)

Error:

---------------------------------------------------------------------------
ClientError                               Traceback (most recent call last)
<ipython-input-377-d15b6de40d9f> in <module>
      4     role_arn = role,
      5     enable_online_store = True,
----> 6     s3_uri = offline_feature_store_bucket
      7 )

~/anaconda3/envs/python3/lib/python3.6/site-packages/sagemaker/feature_store/feature_group.py in create(self, s3_uri, record_identifier_name, event_time_feature_name, role_arn, online_store_kms_key_id, enable_online_store, offline_store_kms_key_id, disable_glue_table_creation, data_catalog_config, description, tags)
    474             )
    475 
--> 476         return self.sagemaker_session.create_feature_group(**create_feature_store_args)
    477 
    478     def delete(self):

~/anaconda3/envs/python3/lib/python3.6/site-packages/sagemaker/session.py in create_feature_group(self, feature_group_name, record_identifier_name, event_time_feature_name, feature_definitions, role_arn, online_store_config, offline_store_config, description, tags)
   3886             Tags=tags,
   3887         )
-> 3888         return self.sagemaker_client.create_feature_group(**kwargs)
   3889 
   3890     def describe_feature_group(

~/anaconda3/envs/python3/lib/python3.6/site-packages/botocore/client.py in _api_call(self, *args, **kwargs)
    355                     "%s() only accepts keyword arguments." % py_operation_name)
    356             # The "self" in this scope is referring to the BaseClient.
--> 357             return self._make_api_call(operation_name, kwargs)
    358 
    359         _api_call.__name__ = str(py_operation_name)

~/anaconda3/envs/python3/lib/python3.6/site-packages/botocore/client.py in _make_api_call(self, operation_name, api_params)
    674             error_code = parsed_response.get("Error", {}).get("Code")
    675             error_class = self.exceptions.from_code(error_code)
--> 676             raise error_class(parsed_response, operation_name)
    677         else:
    678             return parsed_response

ClientError: An error occurred (413) when calling the CreateFeatureGroup operation:

But I tried with creating another feature group with 2100 features but with names of very small lengths as "0", "1", "2", ... "2099"; and it worked. The feature group got created with no errors. Any clue why it fails with regular column names ? TIA