[Connect Update 16 C# Add-in] Saving changes on loaded DgnFile

Hello,

Here's a piece of test code that I was running where I am attempting to add a shape and save the document without opening in GUI. I am not getting any errors, but also not seeing the file change. Am I supposed to save some other way?

            using (DgnDocument dgnDocument = DgnDocument.CreateForLocalFile(FullFileName))
            {
                using (DgnFileOwner dgnFileOwner = DgnFile.Create(dgnDocument, DgnFileOpenMode.ReadOnly))
                {
                    var dgn = dgnFileOwner.DgnFile;
                    StatusInt status;

                    dgn.LoadDgnFile(out status);
                    
                    DPoint3d[] pntsArr = new DPoint3d[4];

                    pntsArr[0] = new DPoint3d(newRange.High.X, newRange.High.Y, 0);
                    pntsArr[1] = new DPoint3d(newRange.High.X, newRange.Low.Y, 0);
                    pntsArr[2] = new DPoint3d(newRange.Low.X, newRange.Low.Y, 0);
                    pntsArr[3] = new DPoint3d(newRange.Low.X, newRange.High.Y, 0);

                    

                    foreach (var modelId in dgn.GetModelIndexCollection())
                    {
                        var model = dgn.LoadRootModelById(out status, modelId.Id);
                        ShapeElement shape = new ShapeElement(model, null, pntsArr);
                        shape.AddToModel();
                        shape?.Dispose();
                        
                        dgn.DoSaveAs(dgnDocument, DgnFileFormatType.Current, true, false);
                        break; 
                       
                    }
                }
            }