Cron jobs are no longer running

Environment: Red Hat Enterprise Linux Server release 6.6 (Santiago)

# crontab -e

Authentication token is no longer valid; new one required
You (root) are not allowed to access to (crontab) because of pam configuration.

there were no changes in /etc/security/access.conf

the problem is root`s expired password
# chage -l root
Last password change                                    : Mar 20, 2015
Password expires                                        : Apr 29, 2015
Password inactive                                       : never
Account expires                                         : never
Minimum number of days between password change          : 0
Maximum number of days between password change          : 40
Number of days of warning before password expires       : 7

# passwd root

and check 
# crontab -l