diff --git a/app/main.py b/app/main.py
index 54b955d..db8801b 100644
--- a/app/main.py
+++ b/app/main.py
@@ -115,8 +115,19 @@ def validate_authorize_credentials():
     else:
         controller.setenvironment(constants.SANDBOX)
 
-    controller.execute()
-    response = controller.getresponse()
+    # Suppress the SDK's XML parsing error (ContentNondeterminismExceededError)
+    # This is a known issue with the authorizenet SDK's PyXB dependency
+    # The error doesn't affect functionality, just creates noise in logs
+    authorizenet_logger = logging.getLogger('authorizenet.sdk')
+    original_level = authorizenet_logger.level
+    authorizenet_logger.setLevel(logging.CRITICAL)
+    
+    try:
+        controller.execute()
+        response = controller.getresponse()
+    finally:
+        # Restore original logging level
+        authorizenet_logger.setLevel(original_level)
 
     if response is None:
         raise ValueError("Could not connect to Authorize.net - check network connectivity")