Re-validate webmail ????

I received an email from: Provider IT Tech as follows:

Your Cox! Web mail version is outdated and has expired.
Failure to Upgrade to the newest Cox! Web mail now will result in a permanent account closure.
According to provision 17.8 of Terms and Conditions, Cox! Web mail may at any time terminate its services for accounts.
Visit ITS Help-Desk Here To re-validate your mailbox .
Note: Failure to comply with 24 hrs might lead to permanent deactivation.
Thank you!
Cox! Web mail

How do I RE-VALIDATE???? Is this legit??? I have no idea what I am expected to do. FWIW I am using OUTLOOK 2016 as my email client. Thanx.