My new account has an unknown user and I cannot access my own account online!!!

My old account is still active online and shows a positive balance (all has been paid on this account).  When I tried to register my new account number it gave me two email addresses that I could use as user names.  These addresses are unknown to me.  Has my new account been hacked?  Am I paying for someone elses cable, internet and TV?  I tried called the help number which should be called anything BUT the help number.  Anyone help!!!