From time to time I get random calls purporting to be on behalf of Virgin Media. Always clearly from someone overseas. They claim they want to review the services I have and probably entice me into some new deal, or whatever. I never let it get that far.
At an early stage they want me to verify who I am by giving a couple of characters from my password.
They phoned me. I don't know they are who they claim to be. With enough calls over a few months they'd have my password. That is how identity theft works.
So as I won't give a password they want me to confirm other stuff like how I pay them.
They just don't get it.
So VM, and indeed other companies, if you want to sell me something by phone, and I'm prepared to even take your call, then by all means tell me what I could have. If I want to take you up on that, I'll call you then I know who I am talking to and will be happy to do the security bit.
Perhaps as you have my email address you'd be better off sending targeted messages to me that way, so I can peruse at my leisure and take you up on stuff if it appeals. But cold calling me, and wanting me to do security is never ever going to get anything other than a blunt response.