Just found out an account I have got frozen. I know TNT doesn't give a reason anymore why they frozen accounts, right?

I had this account more than 1 year now. Well, as far as I know of.

I did changed everything. UN, PW, Pin and even the email.
Well. I did not used any programs or such for this account. Just transferred some stuffs from time to time but not that often.

or maybe the real owner came back and reported?