Windows Hello not working every time 1PW is started

I had run into this issue as well, and before I thought to check in here for the communal wisdom, I managed to solve the issue another way that didn't involve removing or downgrading my 1Password Nightly build installation, though it did involve slightly more work. In the event the problem recurs or it proves useful to the dev team or other users, I'll record the process here.

1. Open 1Password and go to the Settings > Security. Uncheck "Use Windows Hello", close the settings and then press Ctrl+Q on your keyboard to quit 1Password altogether.
2. Open Windows Settings > Accounts > Sign-in options, and deactivate the toggle for "Only allow Windows Hello sign-in for Microsoft accounts on this device" if it is currently active.
3. Navigate up one level in Windows Settings > Accounts and click on "Access work or school". Disconnect any accounts found there. (Only necessary for Microsoft 365/Azure AD users)
4. Right-click the Start button and select "Terminal (Admin)", "Command Prompt (Admin)" or "PowerShell (Admin)", whichever you find there, and at the prompt issue the applicable flavor of the following command:
   • For Command Prompt: %windir%\System32\certutil.exe /DeleteHelloContainer
   • For PowerShell: $Env:windir\System32\certutil.exe -DeleteHelloContainer
5. Press Winkey+R on your keyboard and type tpm.msc in the dialog window that appears, then press the Enter key. Use the toolbar button to show the Action Panel on the right if it isn't already there, and click the "Clear TPM" listing there. Accept the need for the system to immediately reboot and allow it to do so. The boot process length from the power cycle to the lock screen display will roughly double.

This will require you to login to your system for the first time without the benefit of Windows Hello's PIN, facial recognition or biometric authentication, only your account password will suffice. Once that's done, return to Settings > Accounts and reactivate Windows Hello sign-in and re-connect any work or school accounts you may have removed earlier. Finally, open 1Password and toggle "Use Windows Hello" back on, at which point you'll see that the Use TPM option is now restored to its former glory. The next time 1Password starts you will be asked for your Master Password one final time and then be treated to the sweet, sweet comfort of the Windows Hello authentication prompt at long last.

To be sure, this is a draconian means of removing all of the cryptographic tokens stored on your system that facilitate basic user authentication and is not for the faint of heart or those who don't maintain convenient redundant access paths to their account passwords that undergird the Windows Hello abstractions. I was able to accomplish the entire process in around ten minutes (less time than it tooks to type this post, ironically) with the benefit of the 1Password app on my Android phone, which had the passwords needed following the required power cycle. To reiterate, I'm not advocating this as a superior alternative to the solutions others had arrived at earlier in this thread, but rather as a fallback approach in the event it doesn't resolve this problem for you.