Resolution:
Correct the code; then recompile.
Example:
In the following example, the SORT statement references a field. It must reference an array.
           declare s1 as string = "Hello"
           sort s1                        *> Error - s1 is not an array
           declare array = table of byte(5 4 3 2 1)
           sort array                     *> ok - will sort the elements of the array
           perform varying i as byte through array
               display i
           end-perform