I want to delete my old(7years unused, never logged in) Twitter account. I lost the email to it, but it has my name so I would like to delete it. I wrote twitter support twice and told them "This is my old account it's obviously inactive as you can see. I lost the email for the account, but please delete it. I even attached a scan of my passport to prove that it is me. But after 2 requests they still refuse to delete it. In the second request I send them following: https://gdpr-info.eu/issues/right-to-be-forgotten/ which in my understanding means they have to comply with my request.

Their response is we can not delete an account without you owning the original email. But I lost the email and the account has my first and second name and is inactive which excludes some kind of troll request.

Now my jurisdiction is Switzerland, which as far as I understand does not have GDPR, but I presume Switzerland has something equivalent to GDPR. How can I get twitter to delete my account?