Hello babbelmanet​! 👋
I'm sorry that you're running into an issue with 2FA. A time-based one-time password (TOTP) is generated from the following:
- A secret that you save in an authenticator app.
- The current time.
1Password only saves the secret and it doesn't save anything related to the time. Websites that support TOTP 2FA will usually require that you enter the one-time password generated by your authenticator app after you save it in order to confirm that the one-time password was saved correctly. If the time was off on your old device then you wouldn't have been able to enable 2FA since the one-time password would have been wrong from the beginning.
After a while a reinstalled a new Windows version on that machine and since then the 2FA codes are not working anymore.
You'll need to make sure that the date, time, and time zone on your devices are all accurate for where you are in the world. The exact instructions for doing so vary from device to device, but their controls can usually be found in your device settings. The Time.is website can help you verify the accuracy of your date, time and time zone settings.
Once you've verified that the time is correct, using the website in the previous paragraph, check to see if the one-time password is now working. If it isn't then can you check 1Password on all of your devices, do you see the same one-time password on each device? Or do the one-time password differ from device to device?
-Dave