charge to validate sub-account

I cannot access my wife's email account; I get a message to provide a credit card to verify the age of the user of this sub-account. Two Verizon tech said the could not help me; unaware of such an issue. One Yahoo tech said he was not able to access my email account, but explained the new law. IS THIS SOME KIND OF A SCAM? I'm frustrated with all the time spent with no resolution.

Re: charge to validate sub-account
Specialist - Level 2

It sure sounds like a SCAM to me. Could your email account and/or your wife's account been hijacked?  According to this you can have 8 sub accounts, 

is there any chance you have more than 8 setup ? At this point I would not give out your credit card info.