It seems I have more than one Adobe ID Unfortunately, my Kobo eReader seems to have different ID How do I reset my Kobo so I can log in with the Adobe account that I DO know.

go to: kobo.com/help - Troubleshooting Adobe Digital Editions for the process

To check how can reset you Kobo Reader should contact the Support of Kobo or check the help of your Reader. Unfortunately Digital Edition forum whould not can help with this quesiton good.