Challenge setting up the onlykey as fido2/U2F

I recently purchased the onlykey and read through the user manual. However, I am having problems setting up the onlykey as a fido2/U2F. I got the onlykey to work as OTP but I am struggling to get it to work as fido2/U2F. Can someone point me in the right direction.


It works just like any other FIDO2 security key there is no setup required. You just press a button to register, and press a button to authenticate.

Thank you for your response. I am trying to use the onlykey as a security key with my yahoo account. When it asks to insert the security key, I then insert the onlykey and put in the pin to unlock the key. However, yahoo does not recognize the onlykey. I also touch the #1 slot because that is where I want to place the security key. Is there something else that I need to do with the only key app in order to use it as a security key? Again I am newbie and I greatly appreciate your response.

You have to first register security key with the site, when registering a security key the device flashes blue then you press any button to register with the site. After registering, you can log in with the security key.

Thank you. I got the security key working with using a private browser. Again
thank you for the support.