I to had the same problem with my main account took a break from the game came back and my account was banned veteran of three years so when i contacted support i got asked to supply these details..
*First and last name
*PlayNC Login (if possible)
*Postal address
*Email address
*Date of Birth
*20-digits Serial code/25-digit Access key (This was sent to you via email on the date your game account was activated, with a subject header of Game Account Activated.)
*Last 4 digits of the credit card used on your account
20-digits Serial code/25-digit Access key <<< i dont have this wouldnt keep it for 3 years
20-digits Serial code/25-digit Access key <<< not got this either
So i ended up having to make a brand new account up as they would'nt help me with out these details was really annoyed at that big time