problems getting into ntl email account via app

For security reasons i have changed my email address to log into virgin media  from an ntl email to another and have also changed my password. My email address that i use to send and receive emails is an ntlworld address which I can access by going through my Virginmedia account but I can no longer get updated messages or use on the email app. When I go to my email app it says- to use this account you need to verify your identity. -Tap the account below to sign in,( which is my ntl account). It  states there,s a problem signing in to your accounts, enter your password again. i enter the new password but it just goes back to verify your identity. how can I sort this? any ideas.