How did you try to run the code? If you ran code please show the code and/or LOG. (Please post them as TEXT by using the insert code or Insert SAS Code icons in the forum editor).
I did not have any trouble importing the sheet from your XLSX file.
29 proc import datafile="c:\downloads\MIS445FRED-realGDP.xlsx" out=test replace dbms=xlsx;
30 run;
NOTE: The import data set has 285 observations and 2 variables.
NOTE: WORK.TEST data set was successfully created.