Possible insecure network with network solutions

[Brentley Martin <finop@mindspring.com>]

I had purchased a domain name under email address bmartin874@aol.com or
finop@mindspirng.net entitled "mediacontentservices.com" on 10/2/99. On
10/13/99 the domain name showed up under different person's e-mail named
"sicontwo@opsmail.internic.net" How did this person take my domain name?
I have already started the corporation in February and ordered checks,
business cards, tax id etc... How can this have happened?