You can try to unblock yourself using ReCAPTCHA:
This is typically due to making login attempts from a device such as a mobile phones/ipads or email client like Outlook/Thunderbird on a laptop/PC that has an incorrect email address and/or password being used. To protect the email account, server blocks the IP address from which failed logins occurred as a security precaution.
The “Failed cPanel login” block can be triggered two different ways. The first is by making failed login attempts to cPanel login page. In this event, we recommend that you reset your cPanel password and verify the username is correct. IP address block can also be triggered from failed “webmail” logins as well. It is advised to also ensure you are using the correct email address & password for webmail login in addition to cPanel to make sure the block does not continue to happen.
In the event you see a “mod_security” block being triggered, you will need to contact our support. There are many reasons on why a mod_security related block can be triggered, so we’d need to investigate further. The reasons can range from issues with website modules/plugins triggering a SQL injection block to simply too many failed WordPress or Joomla logins.
Please contact Server Support Team for further information on why the IP Address being Blocked