Cannot Install Tahoe Beta 2

Cannot Install Tahoe Beta 2 because Software Update Dialogue Box will not accept my Password (None in my case). Reports: "User interaction required" Recommendations?

BTW: I am using my regular Apple Password. I do not have a separate Developer Password.

Installation has completed login is successful but after 30 secs it returns to login screen

safe mode does the same. tried recovery mode and reinstalled. Still in the login loop.

what are my choices now?

Cannot Install Tahoe Beta 2
 
 
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