hashtags timeline error

Sentry Issue: SADCOLLECT-16

KeyError: 'created_date'
  File "pandas/core/indexes/base.py", line 3803, in get_loc
    return self._engine.get_loc(casted_key)
  File "pandas/_libs/index.pyx", line 138, in pandas._libs.index.IndexEngine.get_loc
    cpdef get_loc(self, object val):
  File "pandas/_libs/index.pyx", line 165, in pandas._libs.index.IndexEngine.get_loc
    return self.mapping.get_item(val)
  File "pandas/_libs/hashtable_class_helper.pxi", line 5745, in pandas._libs.hashtable.PyObjectHashTable.get_item
  File "pandas/_libs/hashtable_class_helper.pxi", line 5753, in pandas._libs.hashtable.PyObjectHashTable.get_item

KeyError: 'created_date'
(9 additional frame(s) were not displayed)
...
  File "django/utils/decorators.py", line 130, in _wrapped_view
    response = view_func(request, *args, **kwargs)
  File "/www/lts2-imi-demo.epfl.ch/git-repo/sadcollect/viewer/views.py", line 142, in hashtags_timeline
    ht_expl = ht_grp.explode(['user', 'hashtags', 'created_date']).explode('hashtags')
  File "pandas/core/frame.py", line 9024, in explode
    if not all(counts0 == self[c].apply(mylen)):
  File "pandas/core/frame.py", line 3804, in __getitem__
    indexer = self.columns.get_loc(key)
  File "pandas/core/indexes/base.py", line 3805, in get_loc
    raise KeyError(key) from err