This statement attempts to update with a cursor that was not declared for update. The database server does not allow this action, as both a security measure that is designed to prevent program errors and a performance feature. To use a cursor with the UPDATE or DELETE statements, you must declare it for update. Review the program logic to make sure that this statement uses the intended cursor.
In an ANSI-compliant database, any cursor can be used for updating; the FOR UPDATE clause is not required (and generates a warning).