diff --git a/models/Cooldown.json b/models/Cooldown.json
index f10e582..f32fc9d 100644
--- a/models/Cooldown.json
+++ b/models/Cooldown.json
@@ -20,14 +20,12 @@
     "expiration": {
       "type": "string",
       "format": "date-time",
-      "description": "The date and time when the cooldown expires in ISO 8601 format",
-      "minimum": 0
+      "description": "The date and time when the cooldown expires in ISO 8601 format"
     }
   },
   "required": [
     "shipSymbol",
     "totalSeconds",
-    "remainingSeconds",
-    "expiration"
+    "remainingSeconds"
   ]
 }
\ No newline at end of file