Since I did not find your meaning, I have done registration which is not right. I am sorry. Therefore, I want to take the necessary procedure for withdrawal from the membership. I will take great care so that the same thing may not be done from now on. I am sorry.
最後の「I am sorry」は、入れない方がいいのではないかと思います。（謝りすぎの感じがあるため）