fixed typo

Change-Id: I5657e67b15cafebd2f1ae5a11804fee613c34641
diff --git a/TestON/tests/CHOtest/CHOtest.py b/TestON/tests/CHOtest/CHOtest.py
index fdee4be..a65bf3c 100644
--- a/TestON/tests/CHOtest/CHOtest.py
+++ b/TestON/tests/CHOtest/CHOtest.py
@@ -1822,7 +1822,7 @@
 
         if not caseResult and main.failSwitch:
             main.log.report("Stopping test")
-            main.stop( mail=main.emailOnStop )
+            main.stop( email=main.emailOnStop )
 
     def CASE72( self, main ):
         """