i bought a new key and did the wrong thing i guess

i went in the game and was on my pb-guide-ban account when i pressed : redeem code

the key was valid..but still get the guide ban on all servers ..

so i guess that i was not smart to do that on banned account

now i try to make a new account on origin..but now the key is already in use it say...
so..does this mean i lost my new key ?

and what is exactly the good way to follow with a new key for bfbc2 ?

thanks if you help me !