To reset 2FA, you should login to your account, then go on My Account >> Security 


In this page, you see "Google Authenticator" and "Security and Notifications".  If you would like to reset  Google Authenticator, first you need to disable  2FA. 

By click on Disable 2FA, you are asked to enter the token.

When you enter it, your two factor authenticator is disabled. 

Now you can set it again. If you don't know how to set Google Authenticator, please read this article. How to set Google Authenticator?