diff --git a/fishy/engine/common/qr_detection.py b/fishy/engine/common/qr_detection.py
index 6651d0c..46ada7d 100644
--- a/fishy/engine/common/qr_detection.py
+++ b/fishy/engine/common/qr_detection.py
@@ -11,7 +11,7 @@ detector = cv2.QRCodeDetector()
 # noinspection PyBroadException
 def get_values(window: WindowClient):
     values = None
-    for _ in range(5):
+    for _ in range(6):
         img = window.processed_image()
         if img is None:
             logging.debug("Couldn't capture window.")
@@ -21,8 +21,7 @@ def get_values(window: WindowClient):
             window.crop = _get_qr_location(img)
             if not window.crop:
                 logging.debug("FishyQR not found.")
-                continue
-            img = window.processed_image()
+            continue
 
         values = _get_values_from_image(img)
         if not values:
diff --git a/fishy/engine/common/window.py b/fishy/engine/common/window.py
index a27614d..393ee4e 100644
--- a/fishy/engine/common/window.py
+++ b/fishy/engine/common/window.py
@@ -65,6 +65,10 @@ class WindowClient:
         if self.scale is not None:
             temp_img = cv2.resize(temp_img, (self.scale[0], self.scale[1]), interpolation=cv2.INTER_AREA)
 
+        # need ot check again after crop/resize
+        if temp_img.size == 0:
+            return None
+
         return temp_img
 
     def processed_image(self, func=None):
diff --git a/fishy/engine/common/window_server.py b/fishy/engine/common/window_server.py
index 67a5dbc..b1abd37 100644
--- a/fishy/engine/common/window_server.py
+++ b/fishy/engine/common/window_server.py
@@ -25,7 +25,7 @@ class WindowServer:
     """
     Records the game window, and allows to create instance to process it
     """
-    Screen = None
+    Screen: np.ndarray = None
     windowOffset = None
     hwnd = None
     status = Status.STOPPED