API-oedialect `to_sql` bug

I was testing the oedialect API, and I tried to run the following script:
https://github.com/OpenEnergyPlatform/examples/blob/master/api/OEP-oedialect_upload_from_csv.ipynb

Unfortunately, I encountered an error which I cannot be able to understand.
For the code in line in[9] (insert data into table)

oedialect (0.0.5.dev0)

Error:

---------------------------------------------------------------------------
ConnectionException                       Traceback (most recent call last)
<ipython-input-9-241a71346142> in <module>()
      2 session = Session()
      3 try:
----> 4     example_df.to_sql(table_name, conn, schema_name, if_exists='replace')
      5     print('Inserted to ' + table_name)
      6 except Exception as e:

/usr/local/lib/python3.6/dist-packages/pandas/core/generic.py in to_sql(self, name, con, schema, if_exists, index, index_label, chunksize, dtype)
   2128         sql.to_sql(self, name, con, schema=schema, if_exists=if_exists,
   2129                    index=index, index_label=index_label, chunksize=chunksize,
-> 2130                    dtype=dtype)
   2131 
   2132     def to_pickle(self, path, compression='infer',

/usr/local/lib/python3.6/dist-packages/pandas/io/sql.py in to_sql(frame, name, con, schema, if_exists, index, index_label, chunksize, dtype)
    448     pandas_sql.to_sql(frame, name, if_exists=if_exists, index=index,
    449                       index_label=index_label, schema=schema,
--> 450                       chunksize=chunksize, dtype=dtype)
    451 
    452 

/usr/local/lib/python3.6/dist-packages/pandas/io/sql.py in to_sql(self, frame, name, if_exists, index, index_label, schema, chunksize, dtype)
   1124                          if_exists=if_exists, index_label=index_label,
   1125                          schema=schema, dtype=dtype)
-> 1126         table.create()
   1127         table.insert(chunksize)
   1128         if (not name.isdigit() and not name.islower()):

/usr/local/lib/python3.6/dist-packages/pandas/io/sql.py in create(self)
    563                 raise ValueError("Table '%s' already exists." % self.name)
    564             elif self.if_exists == 'replace':
--> 565                 self.pd_sql.drop_table(self.name, self.schema)
    566                 self._execute_create()
    567             elif self.if_exists == 'append':

/usr/local/lib/python3.6/dist-packages/pandas/io/sql.py in drop_table(self, table_name, schema)
   1174         if self.has_table(table_name, schema):
   1175             self.meta.reflect(only=[table_name], schema=schema)
-> 1176             self.get_table(table_name, schema).drop()
   1177             self.meta.clear()
   1178 

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/sql/schema.py in drop(self, bind, checkfirst)
    830         if bind is None:
    831             bind = _bind_or_error(self)
--> 832         bind._run_visitor(ddl.SchemaDropper, self, checkfirst=checkfirst)
    833 
    834     def tometadata(

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/base.py in _run_visitor(self, visitorcallable, element, **kwargs)
   1597 
   1598     def _run_visitor(self, visitorcallable, element, **kwargs):
-> 1599         visitorcallable(self.dialect, self, **kwargs).traverse_single(element)
   1600 
   1601 

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/sql/visitors.py in traverse_single(self, obj, **kw)
    128             meth = getattr(v, "visit_%s" % obj.__visit_name__, None)
    129             if meth:
--> 130                 return meth(obj, **kw)
    131 
    132     def iterate(self, obj):

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/sql/ddl.py in visit_table(self, table, drop_ok, _is_metadata_operation)
    998         )
    999 
-> 1000         self.connection.execute(DropTable(table))
   1001 
   1002         # traverse client side defaults which may refer to server-side

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/base.py in execute(self, object_, *multiparams, **params)
    978             raise exc.ObjectNotExecutableError(object_)
    979         else:
--> 980             return meth(self, multiparams, params)
    981 
    982     def _execute_function(self, func, multiparams, params):

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/sql/ddl.py in _execute_on_connection(self, connection, multiparams, params)
     70 
     71     def _execute_on_connection(self, connection, multiparams, params):
---> 72         return connection._execute_ddl(self, multiparams, params)
     73 
     74     def execute(self, bind=None, target=None):

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/base.py in _execute_ddl(self, ddl, multiparams, params)
   1040             compiled,
   1041             None,
-> 1042             compiled,
   1043         )
   1044         if self._has_events or self.engine._has_events:

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/base.py in _execute_context(self, dialect, constructor, statement, parameters, *args)
   1238         except BaseException as e:
   1239             self._handle_dbapi_exception(
-> 1240                 e, statement, parameters, cursor, context
   1241             )
   1242 

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/base.py in _handle_dbapi_exception(self, e, statement, parameters, cursor, context)
   1458                 util.raise_from_cause(sqlalchemy_exception, exc_info)
   1459             else:
-> 1460                 util.reraise(*exc_info)
   1461 
   1462         finally:

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/util/compat.py in reraise(tp, value, tb, cause)
    275         if value.__traceback__ is not tb:
    276             raise value.with_traceback(tb)
--> 277         raise value
    278 
    279 

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/base.py in _execute_context(self, dialect, constructor, statement, parameters, *args)
   1234                 if not evt_handled:
   1235                     self.dialect.do_execute(
-> 1236                         cursor, statement, parameters, context
   1237                     )
   1238         except BaseException as e:

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/sqlalchemy/engine/default.py in do_execute(self, cursor, statement, parameters, context)
    534 
    535     def do_execute(self, cursor, statement, parameters, context=None):
--> 536         cursor.execute(statement, parameters)
    537 
    538     def do_execute_no_params(self, cursor, statement, context=None):

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/oedialect/engine.py in execute(self, query_obj, params)
    308         command = query.pop('command')
    309         return self.__execute_by_post(command, query,
--> 310                                   requires_connection_id=requires_connection_id)
    311 
    312     def executemany(self, query, params=None):

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/oedialect/engine.py in __execute_by_post(self, command, query, requires_connection_id)
    325 
    326         response = self.__connection.post(command, query, cursor_id=self.__id,
--> 327                                 requires_connection_id=requires_connection_id)
    328 
    329         if 'content' in response:

/home/local/RL-INSTITUT/okan.akca/.local/lib/python3.6/site-packages/oedialect/engine.py in post(self, suffix, query, cursor_id, requires_connection_id)
    225 
    226         if 400 <= ans.status_code < 600:
--> 227             raise ConnectionException(json_response['reason'] if 'reason' in json_response else 'No reason returned')
    228 
    229         return json_response

ConnectionException: No reason returned