diff --git a/hub_api/helpers/session_helper.py b/hub_api/helpers/session_helper.py
index 580da42..371e071 100644
--- a/hub_api/helpers/session_helper.py
+++ b/hub_api/helpers/session_helper.py
@@ -8,6 +8,7 @@ import shutil
 import uuid
 import datetime
 import time
+from copy import deepcopy
 from pathlib import Path
 
 sessions = {}
@@ -26,11 +27,12 @@ def expired_sessions_collector(session_timeout_duration):
   """
   while True:
     if bool(sessions):
-      for session_uuid in sessions:
-        _expire = datetime.datetime.strptime(sessions[session_uuid]['expire'], '%Y-%m-%d %H:%M:%S.%f')
+      _sessions = deepcopy(sessions)
+      for session_uuid in _sessions:
+        _expire = datetime.datetime.strptime(_sessions[session_uuid]['expire'], '%Y-%m-%d %H:%M:%S.%f')
         if _expire < datetime.datetime.now():
-          print("session for user: ", sessions[session_uuid]['user'], "expired.")
-          response_path = (Path(__file__).parent / f'response_files/{session_uuid}').resolve()
+          print("session for user: ", _sessions[session_uuid]['user'], "expired.")
+          response_path = (Path(__file__).parent.parent / f'response_files/{session_uuid}').resolve()
           shutil.rmtree(response_path)
           del sessions[session_uuid]
     time.sleep(60 * int(session_timeout_duration))
diff --git a/hub_api/workflow/energy_plus.py b/hub_api/workflow/energy_plus.py
index a85f11d..1fca8a9 100644
--- a/hub_api/workflow/energy_plus.py
+++ b/hub_api/workflow/energy_plus.py
@@ -20,7 +20,7 @@ from hub_api.helpers.session_helper import refresh_session
 class EnergyPlus(Resource, Config):
   def __init__(self):
     super().__init__()
-    self._extensions = ['.geojson', '.citygml']
+    self._extensions = ['.geojson', '.gml']
     self._tmp_path = (Path(__file__).parent / 'tmp').resolve()
     self._response_path = (Path(__file__).parent.parent / 'response_files').resolve()
     self._city = None
@@ -34,7 +34,7 @@ class EnergyPlus(Resource, Config):
       height_field = request.form.get('height_field')
       year_of_construction_field = request.form.get('year_of_construction_field')
       function_field = request.form.get('function_field')
-      function_dictionary = self._dictionaries[request.form.get('function_dictionary_name')]
+      function_dictionary = self._dictionaries[request.form.get('function_to_hub')]
       return GeometryFactory('geojson',
                              path=file_path,
                              height_field=height_field,