Magento 2 site connection errors - Token-Based Authentication

Magento 2 allows uses to use different methods of authentication to be able to access their web APIs. 

For Spark Shipping, OAuth Access Token Authentication is required. To enable this, make sure you follow the steps outlined below: 

In your Magento Admin, go to Stores -> Configuration -> Services -> OAuth -> Consumer Settings -> Allow OAuth Access Tokens to be used as standalone Bearer tokens -> Yes