Error Message:

12 and 24 hour time formats may not be mixed.

Explanation:

You mixed 12- and 24-hour formats in your time specification. If you use the 12-hour format (with AM and PM), the hours must be from 0 to 12. If you use 24-hour format, the hours must be from 0 to 24.

User Action:

Retype the command with either the 12- or 24-hour format.