diff --git a/admin.py b/admin.py
index c1d13ed..bba3470 100644
--- a/admin.py
+++ b/admin.py
@@ -197,7 +197,10 @@ def save_plugin_config(idx):
                 new_cfg[key] = form_val
             continue
         if form_val is None:
-            continue
+            if ftype == "bool":
+                new_cfg[key] = False
+            else:
+                continue
         try:
             if ftype == "int":
                 new_cfg[key] = int(form_val)
@@ -476,7 +479,10 @@ def api_plugin_config(plugin_name):
         form_val = request.form.get(f"config_{key}")
         ftype = field.get("type", "string")
         if form_val is None:
-            continue
+            if ftype == "bool":
+                new_cfg[key] = False  # unchecked checkbox → False
+            else:
+                continue
         if ftype == "secret":
             # Nur überschreiben wenn nicht leer
             existing = cfg.get("plugin_configs", {}).get(plugin_name, {}).get(key, "")