How to remove a dist-tag in npm?

Currently learning npm.

I have 2 dist-tags, beta: 1.0.1 & latest: 1.0.1.

I want to remove beta: 1.0.1 & I'm not able to do it.

I tried the following, doesn't work.

npm dist-tag rm beta 1.0.1  
npm dist-tag rm beta 
npm dist-tag rm 1.0.1

Worst condition, npm docs doesn't have examples on how to remove a dist-tag!

Edit: As suggested, gone through the github page. Contributors asking to update npm. Still didn't work.