Using an Amazon Echo as a hands free phone answering device.

This works for postpaid only, as it using numbersync software

https://www.att.com/support/article/wireless/KM1000851/

And

https://www.att.com/features/numbersync/

Hello @gls1000,

We can definitely provide you with some more information on this. 

Please find the below steps to reset-up the Amazon Echo.

1. Go to your Alexa app or the Alexa portal (http://sm.att.com/34088ae3).
2. Click the Menu icon.
3. Click Settings.
4. Click Communications.
5. Click AT&T.
6. On the next screen, click ‘SIGN IN’ button.
7. Sign in using customer AT&T User ID and Password, then click SIGN IN.
8. Click the checkbox for the Terms and Conditions, then click Link My Account.
9. Confirm the Emergency Address is Correct by clicking Confirm Address.
   • validation of address occurs
10. Emergency Address Saved screen appears, click OK.
11. Select Calling Preferences by clicking AT&T (Current), then SAVE.
    
    Hope this helps!  Please let us know if you have any additional questions.

Thank you for visiting AT&T Community Forums!

Sia, 

AT&T Community Specialist.