Unable to locate statement causing error

When I ran the procedure below, I am running into the following error:
The error is ORA-00936: missing expression
I tried to put DBMS_OUTPUT.PUT_LINE statements to see where it is failing. I received the following output

SQL> exec proc_load_user_privileges
The error is 6
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 1
The error is 3
The error is 4
The error is 6
The error is ORA-00936: missing expression

It looks like right after the loop is done, the error is happening. How can I zero in on the statement that is causing the problems? I tried to run all the sql statements by themselves in sql*plus and they are working fine. I am not sure where the syntax error is. Any help would be greatly appreciated.

Here is the procedure text

CREATE OR REPLACE PROCEDURE proc_load_user_privileges
AS

CURSOR cur_list_of_cols
IS
SELECT column_name FROM user_tab_columns WHERE table_name = 'TEMP_NSDA_USER_PRIVILEGE' AND column_name NOT IN ('SUN_ID', 'NODE_ID', 'OPERATION', 'FIRST_NM', 'LAST_NM', 'FUNCTIONAL_AREA_NM');

CURSOR cur_temp_nsda_user_privilege
IS
SELECT SUN_ID,NODE_ID,OPERATION,FIRST_NM,LAST_NM,FUNCTIONAL_AREA_NM FROM TEMP_NSDA_USER_PRIVILEGE;

v_current_sun_id VARCHAR2(30);
v_current_node_id NUMBER(20);
v_current_privilege_nm VARCHAR2(30);
v_current_user_privilege_val VARCHAR2(30);
v_current_column_name_in VARCHAR2(30);
v_block_str VARCHAR2(500);
v_dynamic_query_handle INTEGER;
feedback INTEGER;
v_curr VARCHAR2(30);
v_operation VARCHAR2(30);
v_first_nm VARCHAR2(30);
v_last_nm VARCHAR2(30);
v_functional_area VARCHAR2(30);

BEGIN
FOR rec_temp_nsda_user_priv IN cur_temp_nsda_user_privilege
LOOP
v_current_sun_id := rec_temp_nsda_user_priv.sun_id;
v_current_node_id := rec_temp_nsda_user_priv.node_id;
v_operation := rec_temp_nsda_user_priv.operation;
v_first_nm := rec_temp_nsda_user_priv.first_nm;
v_last_nm := rec_temp_nsda_user_priv.last_nm;
v_functional_area := rec_temp_nsda_user_priv.functional_area_nm;



IF v_operation = 'UPDATE' THEN
DELETE FROM NSDA_USER_PRIVILEGE_T
WHERE sun_id = v_current_sun_id;
END IF;
DBMS_OUTPUT.PUT_LINE('The error is 6');
FOR current_col IN cur_list_of_cols
LOOP
v_current_privilege_nm:= current_col.column_name;


v_block_str:=
'SELECT ' || v_current_privilege_nm || ' FROM TEMP_NSDA_USER_PRIVILEGE WHERE sun_id = ' || v_current_sun_id || ' AND node_id = ' || v_current_node_id ;


EXECUTE IMMEDIATE v_block_str INTO v_current_user_privilege_val;

BEGIN
SELECT
REPLACE(v_current_privilege_nm, '_', ' ')
INTO v_current_privilege_nm
FROM DUAL;

END;
DBMS_OUTPUT.PUT_LINE('The error is 1');


IF (v_current_user_privilege_val = 'Y')
THEN

INSERT INTO NSDA_USER_PRIVILEGE_T (sun_id, node_id, privilege_nm) VALUES (v_current_sun_id, v_current_node_id, v_current_privilege_nm);

ELSIF (v_current_user_privilege_val IS NOT NULL) AND (v_current_user_privilege_val != 'N')
THEN
v_current_user_privilege_val:= TO_NUMBER(v_current_user_privilege_val);
DBMS_OUTPUT.PUT_LINE('The error is 2');


INSERT INTO NSDA_USER_PRIVILEGE_T
(sun_id, node_id, privilege_nm, user_privilege_value)
VALUES
(v_current_sun_id,v_current_node_id,v_current_privilege_nm,v_current_user_privilege_val);

END IF;
DBMS_OUTPUT.PUT_LINE('The error is 3');



END LOOP;
DBMS_OUTPUT.PUT_LINE('The error is 4');

END LOOP;
DBMS_OUTPUT.PUT_LINE('The error is 5');
EXCEPTION
WHEN OTHERS THEN
DBMS_OUTPUT.PUT_LINE('The error is ' || SQLERRM);
END proc_load_user_privileges;