If you really want to know, it's because you're asking how to bypass security and get back on a website that a lot of us have walked away from.
Also, I assume there was a reason you got banned, and considering all the assholes that they let run rampant, it must have been pretty bad to get permabanned from the whole site.
Now, I don't know you, or what the situation is, and you could be the exception to every rule, but, when I see your post title, I assume that you bring toxicity to the party. We don't want it here, and we don't want to help you bring it back to Reddit either.
Like I said, I don't know you, so maybe none of that's true, but that's one reason why you're getting downvotes.
Not sure permaban always have to do with something severe that you did, I got banned from a subreddit and after a month I asked the mods of the specific sub to let me back in, meanwhile the only thing I did is to comment to this sub with another connected account that I had, the mods all they did is to report me for no reason and reddit mods permabanned both my accounts, I never said anything bad or inappropriate, the site stinks real bad it's simple as that