You have created a custom notification in "Custom Error Pages" and it has not taken effect in the expected amount of time.
Note:
"For Assitance" not included in the variable.
A workaround to "For assistance, contact your network support team. IT Support at:"
Instead add "IT Support at<span>: </span>"
This will still include the "For assistance contact your network support team." As this comes from the custom style sheet loaded by the standard.