Find out the Developer Account I registered an app on, knowing the app's client id, secret, etc.

[2924370]

The subject essentially explains my issue. I have released an app approximately one year ago that uses the Spotify Web API and iOS SDK, but now I am trying to find out which account (email) I used to register the account, the password I know. I have tried logging in to each account I would logically register the app under, but all were empty, which is quite frustrating - I am partially convinced that I have registered the application on one of the accounts that I have checked, but it simply no longer shows up for maybe some database issue reasons...

In case I have used a completely different account, is there any way of finding out the account name for this? I know everything about the application; the client id, secret, callback URIs, etc. I could even run through a token authentication process and read the response in case that helps in any way. 

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In case anyone from Spotify reads this, I would like to point out that the auto-login process on the dashboard is the most annoying 'feature' I have ever encountered when you are trying to iterate through various accounts. Not even deactivating 'Keep me logged in' overrides the one-click authentication process. Only after some modifications in blocking some cookies at specific points have I been allowed to log in on different accounts with the same device. What even is the point of passwords and account protection if it is never requested on the same device ever again? 

[Solid_Tester]

This question might get replies if trimmed down to a more concise one.
(I will remove this reply ASAP)