Unable to reset/delete account

Hey!

I am facing the situation that I apparently am unable to reset my account.

There's a device (Android phone, 1st device, registered just yesterday, only device so far) still connected and this keeps me from starting all over with a new set of keys and another passphrase.
Even though I am pretty certain that I do remember my passphrase correctly, the system won't let me sign in. It might be though, that I mistyped it two times in an identical manner (thick fingers, small glass screen) and thus I am denied access to the account.

After following the path to reset the passphrase / start anew, the system is telling me:
"You can't reset your passphrase, since you have active device or paper keys. The following devices all have the power to change your passphrase.

• Mobile Device
  If you have lost all these devices, please contact"
  After verifying myself on Twitter, I did sign out.
  Well, I have not exactly lost the device, but can't log on anymore as I can't make it post the log in screen.

I uninstalled the app, hoping that this'd remove the "signed in" status somehow and reinstalled it and now seem to be completely screwed. In the app, I can't even try to log in using the passphrase: "There was an error provisioning

You can't authorize by passphrase, since you have established device or paper keys. You can go back and pick a device or paper key, or reset your account entirely."

If I decide to reset the account, I'm taken to the website, where I enter my account name and press "forgotten it?"

I'm then told that "That's unfortunate!" (Well, yes. It somehow is.)
I enter my account name again and press "Reset Password" which then presents me with the information from above that I can't do this as I have active device or paper keys and the mobile device still connected.

Anything I'm doing wrong or am maybe missing?
Is there any way to get this odd status cleaned up so that I can start over?

Thanks a lot in advance for any suggestion / help!

The report involves the Android app's passphrase authorization and the website's account-reset flow; start by reproducing the sequence after uninstalling and reinstalling the app. Trace why the existing mobile device still blocks passphrase authorization or account reset, and verify that the affected account can either sign in or reset cleanly.