Hello
I've sent Bcc messages to about 15 email address in one message, and I sent about 2 or 3 messages of this Bcc messages, so the total is about 55-60 max email addresses in a day. I didn't know that this amount of sending mails can cause this problem.
I've sent two requests and tried with the support (Ticket no. 1232043936), and the problem wasn't solved,to verify that I am the owner of the account, I don't remember each single detail of the mail but I've mentioned the 1st password of my mail, I've answered the secret question, mentioned folders and some of the recent email addresses what else should I do to prove that I am the owner of the mail.
I've never had a hard experience, I remember that this issue had happened before and it was solved without complications.