From https://stackoverflow.com/questions/46689890/why-is-bower-returning-a-410-error-message:

This is because bower has changed the registry url today without a redirect.

You need to edit your .bowerrc file to include this to point to the new url.

{

"registry": "https://registry.bower.io"

}

Note, this is only if you're unable to update your version of bower. If you update bower this should resolve itself.