SQL & PL/SQL

SQL>   1  DECLARE
  2   TYPE CUSTOMER_RECORD IS RECORD (CUSTOMER_ACCT_ID NUMBER,
  3                                                       CUSTOMER_NAME   VARCHAR2(2000));
  4  --CREATE TABLE OF RECORD TYPE
  5    TYPE CUSTOMER_REC IS TABLE OF
  6    CUSTOMER_RECORD
  7   INDEX BY BINARY_INTEGER;
  8  --INSTANCE OF RECORD
  9  LREC_CUSTOMER_RECORD CUSTOMER_RECORD;
 10  --INSTANCE OF TABLE
 11  LT_CUSTOMER_REC CUSTOMER_REC;
 12   BEGIN
 13  --ASSIGN VALUES TO INSTANCE OF RECORD
 14   LREC_CUSTOMER_RECORD.CUSTOMER_ACCT_ID:=10;
 15   LREC_CUSTOMER_RECORD.CUSTOMER_NAME:='BHAGAT';
 16  --INSERT INTO TABLE, VALUES FROM RECORD INSTANCE
 17   LT_CUSTOMER_REC(1):=LREC_CUSTOMER_RECORD;
 18  --OUTPUT
 19   DBMS_OUTPUT.PUT_LINE(LT_CUSTOMER_REC(1).CUSTOMER_ACCT_ID);
 20   DBMS_OUTPUT.PUT_LINE(LT_CUSTOMER_REC(1).CUSTOMER_NAME);
 21*  END;
 22  /
*
ERROR at line 1:
ORA-06550: line 0, column 0:
PLS-00201: identifier 'PLITBLM' must be declared
ORA-06550: line 0, column 0:
PLS-00201: identifier 'PLITBLM' must be declared

Could someone help me out with this error?
Thanks,
Bhagat