diff --git a/rpi/services/clock_service.py b/rpi/services/clock_service.py
index fb8aa1e3..6bf2d170 100644
--- a/rpi/services/clock_service.py
+++ b/rpi/services/clock_service.py
@@ -5,35 +5,35 @@ from models.clock import Clock
 
 class ClockService:
 
-    screen : Screen
-    white_clock : Clock
-    black_clock : Clock
+    _screen : Screen
+    _white_clock : Clock
+    _black_clock : Clock
 
     on_terminated : Callable[[], None]
 
     def __init__(self):
-        self.screen = Screen()
-        self.screen.enableBackground()
-        self.screen.displayMessage("Waiting...")
+        self._screen = Screen()
+        self._screen.enableBackground()
+        self._screen.displayMessage("Waiting...")
 
-    def start(self, time_control : int, increment : int ):
-        self.white_clock = self.__init_clock(time_control, increment)
-        self.black_clock = self.__init_clock(time_control, increment)
+    def start(self, time_control : int, increment : int):
+        self._white_clock = self.__init_clock(time_control, increment)
+        self._black_clock = self.__init_clock(time_control, increment)
 
-        self.white_clock.start()
+        self._white_clock.start()
 
     def stop(self):
-        self.white_clock.stop()
-        self.black_clock.stop()
+        self._white_clock.stop()
+        self._black_clock.stop()
 
     def switch(self):
-        if self.white_clock.is_running():
-            self.white_clock.stop()
-            self.black_clock.start()
+        if self._white_clock.is_running():
+            self._white_clock.stop()
+            self._black_clock.start()
 
-        elif self.black_clock.is_running():
-            self.black_clock.stop()
-            self.white_clock.start()
+        elif self._black_clock.is_running():
+            self._black_clock.stop()
+            self._white_clock.start()
 
     def set_on_terminated(self, callback : Callable[[], None]):
         self.on_terminated = callback
@@ -45,11 +45,11 @@ class ClockService:
         return clock
 
     def __tick(self, formatted_time : str) -> None:
-        self.__update_screen(f"W {self.white_clock.clock_to_str()} \n B {self.black_clock.clock_to_str()}")
+        self.__update_screen(f"W {self._white_clock.clock_to_str()} \n B {self._black_clock.clock_to_str()}")
 
     def __terminate(self) -> None:
         self.__update_screen("Time is over !")
         self.on_terminated()
 
     def __update_screen(self, message : str) -> None:
-        self.screen.displayMessage(message)
\ No newline at end of file
+        self._screen.displayMessage(message)
\ No newline at end of file
diff --git a/rpi/services/game_service.py b/rpi/services/game_service.py
index c445567b..a7285e97 100644
--- a/rpi/services/game_service.py
+++ b/rpi/services/game_service.py
@@ -8,7 +8,6 @@ from models.exceptions.ServiceException import ServiceException
 from models.game import Game
 from services.clock_service import ClockService
 
-
 class GameService:
 
     _game : Game
@@ -41,7 +40,6 @@ class GameService:
 
     def stop(self):
         self._clock_service.stop()
-        self._detection_service.stop()
         self._led.off()
         self._notify()
         self._has_started = False