diff --git a/troubleshooting.py b/troubleshooting.py
index a5325e8..4959c35 100644
--- a/troubleshooting.py
+++ b/troubleshooting.py
@@ -190,9 +190,9 @@ def https_check(params, authentication):
                                 break
         
 
-            expiry_date = cert_obj.not_valid_after
+            expiry_date = cert_obj.not_valid_after_utc
             # Check if expiry date is past
-            if expiry_date < datetime.datetime.now():
+            if expiry_date < datetime.datetime.now(datetime.timezone.utc):
                 return {"result": "Certificate is expired"}
         else:
             return {"result": "No certificate found"}