can't access email saub-=account directly

[MrCurious2]

I have a main ewmail account and a few sub-accounts connected to it.  I can retrieve all messages from all accounts with Thunderbird.  But when I log on to the Verizon.net page with the problem email name, it tells me "account is locked" and then gives me an "opportunity " to unlock it by answering some questions whose answers I supplied when I first signed up.

I answer them correctly, and Verizon sends an mail to my main account containing a 4-digit "temporary pin".  But when I enter the temporary pin that still does not unlock the problematic account!  HELP!!!!   How can I fix this problem?