In 2013 I made an alternative twitter account to my main, unsure why I did that, we'll never know. 5 years later, I went to delete the account after finding it again, but found I had no access to the email to reset the password that I had forgotten - oh no.
I'm from the United Kingdom, so I thought I would be able to have the account deleted via GDPR, under the right to be forgotten but found very quickly that trying to do that via Twitter is near impossible, wonderful.
At this point, you may be asking yourself why are you going through all this effort to have an old account deleted int the first place? Well, because there's a mildly, not entirely, inappropriate photo on there that shows up when you google my name. If I have the account deleted, I can have Google remove the image from search results too, like it never existed. I'll explain how to do that in a separate post.
So here's how you do it, surprisingly simple really. Go through the password reset process, and enter what you think the email address is. The closer you are, the more likely you are to succeed. It's also super useful if there is something on the account that matches yourself, such as your name or a picture of yourself. Just something Twitter Support can identify the account to you with. Assuming you get the email wrong (as I assume you would since you're reading this), you'll get an email back from twitter support like this one.
The important part of this email is this bit If this is an organisation or company account, reply to this email and let us know. You're going to want to ignore the fact it wants you to be an organisation or company account, simply just reply with something along the lines of you lost access to the account a long time ago, you've tried to guess the email/password etc but you can't, you don't want access to the account you just want to delete it and that you're able to provide some ID to prove who you are - you'll need ID or they won't do this.
Make sure you reply to the email with the email address you entered in the forgot password page as they need to verify you have access to that email, I made that mistake and it took a bit longer because of that.
You're going to hopefully end up with a reply from someone stating they've received the request to deactivate the account and you'll need to send in some stuff for them to process it, the email will look like this (or similar)
Upload your ID, I used my passport and blurred everything out other than my photo, my name and my date of birth and they accepted it, but I believe they only need your name and photo to verify who you are. You should receive an email a few hours later depending on the time of date telling you if the account will be deactivated or not.
Once it's deactivated, the account will delete after 30 days - I imagine this is just in case you try and jack someone else account, who knows but my account is deleted finally.
Post Edit 09/09/2018: There was a mistake in this post where I put 'password' instead of passport.