I anwered my own question...ℹ
I just checked on the help section of the Text Pane in SmartArt Graphic. It is a compatibility issue. I copied the explanation from the Help section in case any of you encounter the same issue again. I couldn't solve the issue but I try not saving the file (which is dangerous at time) until I am done inserting the text into the selected SmartArt Graphic. It worked.
SmartArt Graphics are incompatible with earlier versions of Office. Instead, the SmartArt Graphics are converted to pictures when you:
- Save a file in an earlier Office file format, such as Word 97–2004 Document.
- Use the Open XML file format converter to open a file in an earlier version of Office.You can download the Open XML File Format Converter for Mac from the Downloads area on the Microsoft Web site (http://www.microsoft.com/mac/download).
After the SmartArt graphic converts to a picture, you cannot edit its contents or change the layout.
If you later save the file in the Office 2008 format, the picture reverts to a SmartArt Graphic.
Note SmartArt Graphics are compatible with the 2007 Microsoft Office system (for Windows).