npm config delete <setting> is deleting my .npmrc file

If I create an .npmrc file by:

touch /Users/$USER/.npmrc

and do an:

ls -a
npm config set proxy ${proxy_url}

I can see my proxy set in my .npmrc file. However, if I switch networks and I want to delete it, I tried:

npm config delete proxy

And when I do an:

ls -a

My entire .npmrc file appears to have been deleted, which is giving me an

npm ERR! Error: ENOENT, unlink...

Can anyone help? I just want to delete that setting in my .npmrc file, not delete the entire file.