Cannot Authorize New Device - Activation Failed/Limit Reached

Hello Community,

I am having trouble authorizing my new computer/e-reader using my Adobe ID in Adobe Digital Editions (ADE).

I suspect I may have reached the maximum number of authorized devices, as I get a generic "Activation Failed" message (or "E_ACT_NOT_FULFILLED").

I need to deauthorize an old computer that I no longer use, but I cannot access it.

Could someone please provide guidance or steps on:

How to remotely deauthorize old devices connected to my Adobe ID?

What is the best way to contact Adobe support if remote deauthorization is not possible?

Any advice on clearing an activation slot would be highly appreciated! Thank you.