I've created a custom section where I'm displaying content nodes flagged for translation. I am then rendering the edit form which you would see in the Content section.

I've then added a button to trigger a save event using contentResource.sendToPublish(content, isNew, files) as shown in the code below

angular.module("umbraco")
.controller("StagingEditController",
    function ($scope, $routeParams, $http, contentResource, notificationsService) {
        $scope.loaded = false;

        $scope.page = {};

        if ($routeParams.id === -1) {
            $scope.content = {};
            $scope.loaded = true;
        } else {
            $scope.content = {};

            contentResource.getById($routeParams.id)
                .then(function (response) {
                    $scope.content = response;
                });
        }

        $scope.preview = function(content) {
            console.log('preview', content);
        }

        $scope.save = function(content) {
            contentResource.sendToPublish(content, false, [])
                .then(function(response) {
                    console.log('sendToPublish', response);

                    notificationsService.success("Document sent for approval", "");
                }, function(err) {
                    notificationsService.success(err, "");
                });
        }
    });

Yet when attempting to save I am getting the following error message

Authorization error: Unauthorized access to URL: 
/umbraco/backoffice/UmbracoApi/Content/PostSave
with data: 
{"key":"contentItem","value":{"id":1062,"properties":[{"id":142,"alias":"pageTitle","value":"About"},{"id":141,"alias":"metaDescription","value":"Lorem ipsum dolor sit amet, consectetur adipiscing elit. Fusce sed posuere urna."},{"id":143,"alias":"umbracoNaviHide","value":"0"},{"id":144,"alias":"hideFromSitemap","value":"0"}],"name":"About","contentTypeAlias":"standardPage","parentId":1055,"action":"sendPublish","expireDate":null,"releaseDate":null,"templateAlias":"StandardPage"}}
Contact your administrator for information.

Wondering if anyone has come across this issue before and managed to solve it?