Difference displaying a String vs PIC X

Hi,

I have some texts defined as System.String or String inside Visual COBOL for Visual Studio 2012 and some defined as pic x.

I can not find how to display a variable defined as string using line and column without receiving a compilation error COBCH030. And the display of the pic x is shown in a different color (green) than the display of the string (white)

01 text1 type System.String.
01 thetext pic x(50).
       procedure division.
           set text1 thetext to "Hello World".
           display text1::Trim.
                     
           display thetext line 20 position 20.

Regards,