Bringing data from Rapidmail to Salesforce Marketing Cloud

Question

We are trying to get the recepient activity data from Rapidmail to SFMC using the below code. It throws an error saying that >Script.Util.HttpResponse{"type":"http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html","title":"Not Acceptable","status":406,"detail":"Unable to resolve Accept header to a representation"}"

          req.emptyContentHandling = 0;
          req.retries = 2;
          req.continueOnError = true;
          var baseIt = Platform.Function.Base64Encode(config.username + ":" + config.password);
          var auth = "Basic " + baseIt;
          req.setHeader("Authorization" , auth);  
          req.setHeader("Accept-Language", "*");
          req.method = "GET";
       
  var res = req.send();
  Write(res.content);```

Could you please let me know how to solve the issue.

Thanks,
Nikhila