Table not declared error even though I'm able to view it in database

Question

Hi,
I'm trying to compile a form with the following code in a when button pressed trigger.I get the error that Trust_tab should be declared even though I am able to view the contents in sql plus. Why is it?
REGISTER_BLK.TRUST_CODE:=:GLOBAL.TRUSTCODE;
declare
m number;
begin
if CHECKBOX_CHECKED('REGISTER_BLK.CHK_BETWEEN_DATES') =true and (:REGISTER_BLK.date_from is null or :REGISTER_BLK.date_to is null )THEN
if :REGISTER_BLK.date_from is null then
m:=show_alert('alert61');
-- message('Please Enter Date');
previous_item;
go_item('register_blk.date_from');
raise form_trigger_failure;
elsif :REGISTER_BLK.date_to is null then
-- message('Please Enter Date');
m:=show_alert('alert61');
previous_item;
go_item('register_blk.date_to');
raise form_trigger_failure;
end if;
else
DECLARE
n number;
PL_ID PARAMLIST;
CONDITION VARCHAR2(500);
CHANGED_MODE_TYPE VARCHAR2(20);
MODECODE NUMBER;
TRUSTNAME VARCHAR2(60);
TNAME VARCHAR2(60);
TRUST_CODE VARCHAR2(1);
MODE_TYPE VARCHAR2(15);
DATE_FROM DATE;
DATE_TO DATE;
CONDITION1 VARCHAR2(200);
MAXDATE DATE;
BEGIN
IF NOT Id_Null(get_parameter_list('ABC')) THEN
Destroy_Parameter_List('ABC');
END IF;
PL_ID:=create_parameter_list('ABC');
IF
CHECKBOX_CHECKED('REGISTER_BLK.CHK_BETWEEN_DATES')= TRUE
--THEN
and :REGISTER_BLK.date_to is not null
and :REGISTER_BLK.date_from is not null then
DATE_FROM:=:REGISTER_BLK.DATE_FROM;
DATE_TO :=:REGISTER_BLK.DATE_TO;
SELECT TRUST_NAME INTO TRUSTNAME FROM TRUST_TAB
WHERE TRUST_CODE=:REGISTER_BLK.TRUST_CODE;
:REGISTER_BLK.TNAME:=TRUSTNAME;
CONDITION:= ' HAVING DV.TRUST_CODE = '|| :REGISTER_BLK.TRUST_CODE ||
' AND MAX(MAXDATE) >= ' ||''''||TO_CHAR(:REGISTER_BLK.DATE_FROM,'DD-MON-YY')||'''' ||
' AND MAX(MAXDATE) <= ' ||''''||TO_CHAR(:REGISTER_BLK.DATE_TO,'DD-MON-YY')||'''';
-- MESSAGE(CONDITION);
Add_parameter('ABC','paramform',TEXT_parameter,'no');
Add_parameter('ABC','P_CODE',TEXT_PARAMETER,:REGISTER_BLK.TRUST_CODE);
Add_parameter('ABC','P_datefrom',TEXT_PARAMETER,:REGISTER_BLK.DATE_FROM);
Add_parameter('ABC','P_dateto',TEXT_PARAMETER,DATE_TO);
--Add_parameter('ABC','WHERE_CLAUSE',TEXT_PARAMETER,CONDITION);
--Add_parameter('ABC','HAVING_CLAUSE',TEXT_PARAMETER,CONDITION1);
Run_Product(REPORTS,'new_rec2.rdf',ASYNCHRONOUS,RUNTIME,
FILESYSTEM,PL_ID,NULL);
ELSIF
CHECKBOX_CHECKED('REGISTER_BLK.CHK_BETWEEN_DATES') = FALSE
--THEN
or :REGISTER_BLK.date_to is null
or :REGISTER_BLK.date_from is null then
n:=show_alert('alert62');
previous_item;
go_item('REGISTER_BLK.CHK_BETWEEN_DATES');
--raise form_trigger_failure;
-- MESSAGE('Select atleast One Option for Generation of Report');
-- MESSAGE('Select atleast One Option for Generation of Report');
RAISE FORM_TRIGGER_FAILURE;
END IF;
END;
end if;

Answer 1

Guess you are connected with wrong schema..
have you test with another test button ,simply just count the record into local
vraible with sql in another test button??
DECLARE
  cnt    NUMBER;
BEGIN
SELECT COUTN(*) INTO cnt
  FROM  trust_tab;
message(cnt);
END;If the same prob persist check yours connectivity from where you are connected.
Khurram