Update vsts-npm-auth with new username and password

I have installed the vsts-npm-auth package using following command:

npm install -g vsts-npm-auth --registry https://registry.npmjs.com

And I ran vsts-npm-auth -config .npmrc command to set the credential but I am facing below error:

Now I need to update the credential but it always fetches the existing credential. Is there any way to send PUT request and update the credential ?

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