Oracle Message ORA-06571 - Function string does not guarantee not to update database

ERRORFunction string does not guarantee not to update database
CAUSEThere are two possible causes for this message: * A SQL statement references a packaged, PL/SQL function that does not contain a pragma that prevents the database from being updated. * A SQL statement references a stand-alone, PL/SQL function that contains an instruction to update the database.
ACTIONIf the referenced function is a packaged, PL/SQL function: Recreate the PL/SQL function with the required pragma; be certain to include the Write No Database State (WNDS) argument in the argument list of the pragma. If the referenced function is a stand-alone, PL/SQL function: Do not use the function.