Npm login with scripts

Hi, I’m new in travis community.
I have a question as i say in the question’s title.
I’m using travis to deploy a npm package (package of a monorepo) on git tags.
I’ve already set the deploy on tags and standard npm commands but i can’t login to npm.
I tried to use the .npmrc that i use also on my pc but nothing.
How can I do that?

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