Don´t reset items when clicking change button

app.py

@@ -40,7 +40,7 @@ def index():
             item4 = 0
             item5 = 0
             item6 = 0
-        else:
+        elif wertfloat != -2:
             gesamtwert += wertfloat
             gesamtwert = round(gesamtwert, 2)
             if gesamtwert > 0:
@@ -91,5 +91,13 @@ def favicon():
         'favicon.ico', mimetype='image/vnd.microsoft.icon')
 
 if __name__ == "__main__":
+    directory = './log'
+    if not os.path.exists(directory):
+        # Create the directory
+        os.makedirs(directory)
+    
+    logger = logging.getLogger(__name__)
+    logging.basicConfig(filename='./log/example.log', encoding='utf-8', level=logging.DEBUG)
+
     logging.info('Starting erdbeerhannah v1.0')
     app.run(debug=True, host='0.0.0.0')