Can't move Windows 11 Pro key to new machine

I'm in the middle of building a new PC and am unable to move my Windows 11 Pro license to it. I have verified with cmd that it is Retail channel and license, IIRC it was purchased as Windows 10 Pro and upgraded. On the system activation page it says "Windows is activated with a digital license linked to your Microsoft account."

This is a retail license I purchased several years ago. I retrieved the key from the old machine using Regedit. If I try to enter this into the Activation settings page on the new PC with "Change Product Key" it says "We can't activate Windows on this device because you don't have a valid digital license or product key. If you think you do have a valid license or key, select Troubleshoot below. (0x803fa067)"

Hitting the troubleshoot button on the system activation page says "We weren't able to activate Windows on this device." Selecting "I changed hardware on this device recently" on the new PC says "We can't find any devices linked to your Microsoft account that can be used for reactivating the device you're using right now. Make sure you're signed in with the same Microsoft account you linked to the Windows 10 digital license on this device or try again later." Clicking "See other devices linked to your Microsoft account" bring up the Reactivate Windows page with the message "We can't reactivate Windows from these devices." I have verified that both machines are linked into the same account and show up in my devices list. I removed the old PC from devices hoping that would help, but it has made no difference. It took a little bit but I was ale to get the PC to show up on my account again, though with less details then had been there previously (it may still be updating.)

I have followed the link to the "Get Help" app, but when I sign in it says "Sorry, but we're having trouble signing you in." "AADSTS500200: User account 'MYACCOUNTHERE' is a personal Microsoft account. Personal Microsoft accounts are not supported for this application unless explicitly invited to an organization."

I tried calling Microsoft support numbers fort the US, and after a great deal of time and effort eventually got past the AI which kept sending me to the directions I had already followed whenever I use the word "activation." I eventually figured out how to get someone on the line and after explaining my problem I was then put on hold for them to transfer me for help, after ~30 minutes the hold music stopped and it went silent. Waited another 10 minutes and nothing so hung up and called again. Could not get them to forward my call to a person again and now whenever I call one of their support numbers it says "Hello, thanks for calling Microsoft, for assistance with Windows Support please visit us online at help.microsoft.com. Thanks for calling Microsoft, have a good day." and hangs up on me. I'm absolutely livid at this as it seems they've flagged my number to ignore it now and I'm left with no way to contact Microsoft support to get my issue resolved.