I'm trying to do the admin advanced Use Basic Logic Checkbox Formulas

This is what its asking 

Ensure that an opportunity can only be created if its CloseDate is today or later.

• Create a validation rule:
  • Object: Opportunity
  • Name: Close_Date_Alert
  • Criteria (both must be true):
    • IsClosed is not selected
    • CloseDate is before today
  • Error message: The close date must be today or later (we won’t check this)

This is the error message I get

Challenge not yet complete in My Trailhead Playground

We expected the validation rule to prevent creating an opportunity with yesterday as the CloseDate, but it didn’t. Make sure the validation rule fires when CloseDate is before today.

The formula I thought was right is AND( IsClosed , CloseDate > TODAY() )

What am I missing.  Been trying for 2 days to figure it out.  Any help would be appreciated #AwesomeAdmins #Trailhead Challenges