You may run into following error while trying login in cPanel/WHM account:
"This copy of cPanel / WHM is a trial version and will expire at the end of the trial term. You will need to upgrade to a paid copy of cPanel / WHM to continue using the software after that term"
Try below steps to get it resolved:
1. Browsed http://www.cpanel.net/apps/verify and entered main IP address of server to verify cPanel license. Make sure that the license if Active.
2. Run /usr/local/cpanel/cpkeyclt if license is active.
Go through below step if above steps does not resolve your issue:
Check for the existence of /var/cpanel/trial. If this file exists, you should remove it and run /usr/local/cpanel/cpkeyclt. However, I would recommend to contact license provider if any of above steps does not resolve issue.