Access B & N Digital Library in ADE/Kobo - Username & Unlock Code Not Working

My second Nook GlowLight recently broke, so I purchased a Kobo Clara HD. I have 3 ebooks I've purchased from Barnes & Noble in the last 18 months that I'd like to put on my Kobo.

I downloaded the Nook app for Windows 10, & I downloaded each of the 3 books. I located the files & uploaded them into 3 different de-DRM apps, but the apps never recognized my B & N username &/or password. I updated my B & N password, logged out & in of B & N as well as the Nook app, restarted the apps, & uninstalled & reinstalled the Nook app to no avail. I tried using my full name & credit card number for the username & PW, respectively, but this didn't work either, even after confirming that the information I used was also listed as the default in my B & N account & on each book's order.

I tried uploading the Nook files directly to ADE, but my username & unlock code for the books did not work. I tried every combination of my name--with & without spaces, my CC number, the order number(s), my B & N username, & my B & N password to no avail. I uninstalled & reinstalled ADE, unauthorized & reauthorized my computer & restarted my computer several times throughout this whole process.

I called B & N, & they said they could not help me. How can I move my B & N digital library to ADE &/or my Kobo?