Error Message and Can’t Connect to Twitter

We have uploaded the plug-in and have tried several times to get it to work with no avail. When we click Twitter, nothing happens (no pop-up) but this populates in the log:

25-10-2018 02:59:10 AM Connection error: <?xml version=”1.0″ encoding=”UTF-8″?><errors><error code=”415″>Callback URL not approved for this client application. Approved callback URLs can be adjusted in your application settings</error></errors>

We have added every callback url we can image to the Twitter app but the plug-in itself won’t let us do anything. we have clicked reset – nothing is working!