Just have the usual things ready with you before you call up.
-Member ID
-Name on the account (They may ask for handle names.)
-Date of Birth
-Full Address
-Playonline Registration Code (Please make sure you have this with you.)
Depending on how busy the higher ups are during the time you call, they may or may not forward you to one, but the rep/manager will ask you a few questions regarding your account such as:
-Name of your character and mules (Make sure they get the spelling correct.)
-Name of your original server
-Date and time you last logged in
-Date and time you were hacked/kicked off
-Last zone/area you were in right before you were hacked
-Your ISP (Internet Service Provider)