Frm-40735: When-validate-item trigger raised unhandled exception ORA-12516

Declare
	Lb_Flag	Boolean;
	Li_Flag	Number;
	Lt_Id		Timer;
	Lt_Id1	Timer;
	Li_Count	Number;
	Li_Count1   Number;
	Li_Msg	Number;
	Al_Button   Number;
	L_month     Number;
	L_Year      Number;
	Lv_Status   Varchar2(3);
	Lv_Status1  Varchar2(3);
	T_Timer     Timer;
  Lc_Found    Varchar2(1);
  Li_Button   Number;
	Ld_Sysdate  Date;
	lv_err_msg varchar2(100);
		
BEGIN

IF Upper(Item_Name) = 'CTL_BLK.TXT_VEP_NO' then
 	
   declare
         cursor cur_prod is select prd_code,stn_wdn_tag,process_date,truck_no
	                   from   t_despatch_det
	                   where vep_no = :txt_vep_no
	                         and frm_wh_code = 'TN185';
	                         
	       cursor cur_acc_dt is  select max(PROD_PRIO_SET_DATE)
												       from t_days;
												       
	       cursor cur_trkchk(lv_truckno varchar2) is select nvl(count(*),0)
	                            from t_truck_time
	                            where vep_no = :txt_vep_no
	                            and truck_no = lv_truckno;
	       
	       acc_date date;		       
         prc_date date;
	       lv_prd number;
	       lv_stn_wdn_tag number;       
	       lv_truckno varchar2(15);
	       
   Begin

BREAK;

    open cur_prod;
    fetch cur_prod into lv_prd,lv_stn_wdn_tag,prc_date,lv_truckno;
    close cur_prod;
    
    if lv_prd is not null then
       if lv_prd not in (91,82) then
			    AL_BUTTON :=FN_ALERT_SETTING('AL_NOTE','PRODUCT STATUS','NOT ALLOWED OTHERTHAN GYPSUM PRODUCTS ' , 'OK');
          raise form_trigger_failure;
       else
       	  open cur_trkchk(lv_truckno);
    	    fetch cur_trkchk into lv_truckno;
    	    close cur_trkchk;
    	    if lv_truckno <> 0 then
			       AL_BUTTON :=FN_ALERT_SETTING('AL_NOTE','TRUCK STATUS','THIS TRUCK ALREADY SEND OUT FROM PLANT' , 'OK');
             raise form_trigger_failure;
          else
	           open cur_acc_dt;
	           fetch cur_acc_dt into acc_date;
	           close cur_acc_dt;
             if to_date(prc_date,'dd/mm/rrrr') <> to_date(acc_date,'dd/mm/rrrr') then
                AL_BUTTON :=FN_ALERT_SETTING('AL_NOTE','Invoice Printing Status','Invoice Date Changed' , 'OK');
                raise form_trigger_failure;
             else
 	              pr_inv_gen;
             end if;  
          end if;   
       end if;
    ELSE   
	     AL_BUTTON :=FN_ALERT_SETTING('AL_NOTE','VEP STATUS','VEP NUMBER DOESNOT EXIST ' , 'OK');
       raise form_trigger_failure;
    end if;

--  pr_inv_gen;
   end;
END IF;	
	
null;
END;