react-native-keychain: Failure on setGenericPassword()

Attempting to get setup with react-native-keychain but I am receiving the error below.

TypeError: Cannot read property 'setGenericPasswordForService' of undefined(…)

I’ve installed the npm library and linked it with rnpm. I checked my Libraries folder in XCode to confirm RNKeychain.xcodeproj was installed and I can see the library installed in the Linked Binaries as well.

import Keychain from 'react-native-keychain';

export default class Init extends Component {
  componentDidMount() {
        var username = 'zuck';
    var password = 'poniesRgr8';

    Keychain
        .setGenericPassword(username, password)
        .then(function() {
                console.log('Credentials saved successfully!');
          }).catch(function(error) {
            console.log('Could not set Generic Password. ', error);
          });
  }
}