I have an error inserting data into table through store procedure??

[asifNewbie]

I have created table like this...

CREATE TABLE INVOICEMASTER(INVOICEID INT IDENTITY(1,1),EXPORTER_REF INT,CONSIGNEE_REF INT,BUYER_REF INT,AGENT_REF INT,INVOICENO VARCHAR(20),INVOICEDATE DATETIME,EXPORTERSBILLREF VARCHAR(20),BUYERORDERNO VARCHAR(200),BUYERORDERDATE DATETIME,OTHER_REFERENCES VARCHAR(30),COUNTRYOFORIGIN VARCHAR(50),COUNTRYOFDESTINATION VARCHAR(50),PRECARRIAGEBY NVARCHAR(100),PLACEOFRECEIPT NVARCHAR(100),VESSEL_FLIGHTNO NVARCHAR(100),PORTOFLOADING NVARCHAR(100),PORTOFDISCHARGE NVARCHAR(100),FINALDESTINATION NVARCHAR(100),TERMSOFDELVIERYNPAYMENT NVARCHAR(400),DISCOUNTLABEL VARCHAR(100),DISCOUNTRATE DECIMAL(4,2),DISCOUNTAMOUNT DECIMAL(10,3),INVOICETOTAL DECIMAL(14,3),AMOUNTINWORDS NVARCHAR(200),LCNO NVARCHAR(200),REMARKS NVARCHAR(400),INVOICELABEL VARCHAR(100),PRIMARY KEY(INVOICEID))

CREATE TABLE INVOICECHILD1 (INVOICEREF INT REFERENCES INVOICEMASTER (INVOICEID), MARKSANDCONTAINERSNO NVARCHAR (200), NUMBEROFPKGS VARCHAR (100), DESCRIPTIONOFGOODS NVARCHAR (400),THICKNESS VARCHAR(100),COLOUR VARCHAR(50),SELECTION VARCHAR(30),SIZE NVARCHAR(300),UOM VARCHAR(10),CURRENCYDESC VARCHAR(30))

and the below is store procedure query..

CREATE PROCEDURE INSERT_INVOICE(@EXPORTER VARCHAR(150),@CONSIGNEE VARCHAR(150),@BUYER VARCHAR(150),@AGENT VARCHAR(150),@INVOICENO VARCHAR(20),@INVOICEDATE DATETIME,@EXPORTERSBILLREF VARCHAR(20),@BUYERORDERNO VARCHAR(200),@BUYERORDERDATE DATETIME,@OTHER_REFERENCES VARCHAR(30),@COUNTRYOFORIGIN VARCHAR(50),@COUNTRYOFDESTINATION VARCHAR(50),@PRECARRIAGEBY NVARCHAR(100),@PLACEOFRECEIPT NVARCHAR(100),@VESSEL_FLIGHTNO NVARCHAR(100),@PORTOFLOADING NVARCHAR(100),@PORTOFDISCHARGE NVARCHAR(100),@FINALDESTINATION NVARCHAR(100),@TERMSOFDELVIERYNPAYMENT NVARCHAR(400),@MARKSANDCONTAINERSNO NVARCHAR (200), @NUMBEROFPKGS VARCHAR (100), @DESCRIPTIONOFGOODS NVARCHAR (400),@THICKNESS VARCHAR(100),@COLOUR VARCHAR(50),@SELECTION VARCHAR(30),@SIZE NVARCHAR(300),@UOM VARCHAR(10),@CURRENCYDESC VARCHAR(30),@DISCOUNTLABEL VARCHAR(100),@DISCOUNTRATE DECIMAL(4,2),@DISCOUNTAMOUNT DECIMAL(10,3),@INVOICETOTAL DECIMAL(14,3),@AMOUNTINWORDS NVARCHAR(200),@LCNO NVARCHAR(200),@REMARKS NVARCHAR(400),@INVOICELABEL VARCHAR(100))
AS
BEGIN TRANSACTION

DECLARE @EXPORTER_REF AS INT
SET @EXPORTER_REF = 0
SELECT @EXPORTER_REF = EXPORTERID FROM EXPORTER WHERE EXPORTERNAME=@EXPORTER

DECLARE @CONSIGNEE_REF AS INT
SET @CONSIGNEE_REF = 0
SELECT @CONSIGNEE_REF = CONSIGNEEID FROM CONSIGNEE WHERE CONSIGNEENAME=@CONSIGNEE

DECLARE @BUYER_REF AS INT
SET @BUYER_REF = 0
SELECT @BUYER_REF = BUYERID FROM BUYER WHERE BUYERNAME=@BUYER

DECLARE @AGENT_REF AS INT
SET @AGENT_REF = 0
SELECT @AGENT_REF = AGENTID FROM AGENT WHERE AGENTNAME=@AGENT

INSERT INTO INVOICEMASTER(EXPORTER_REF,CONSIGNEE_REF,BUYER_REF ,AGENT_REF,INVOICENO,INVOICEDATE,EXPORTERSBILLREF, BUYERORDERNO,BUYERORDERDATE,OTHER_REFERENCES,COUNT RYOFORIGIN,COUNTRYOFDESTINATION,PRECARRIAGEBY,PLAC EOFRECEIPT,VESSEL_FLIGHTNO,PORTOFLOADING,PORTOFDIS CHARGE,FINALDESTINATION,TERMSOFDELVIERYNPAYMENT,DI SCOUNTLABEL,DISCOUNTRATE,DISCOUNTAMOUNT,INVOICETOT AL,AMOUNTINWORDS,LCNO,REMARKS,INVOICELABEL) VALUES (@EXPORTER_REF,@CONSIGNEE_REF,@BUYER_REF,@AGENT_RE F,@INVOICENO,@INVOICEDATE,@EXPORTERSBILLREF,@BUYER ORDERNO,@BUYERORDERDATE,@OTHER_REFERENCES,@COUNTRY OFORIGIN,@COUNTRYOFDESTINATION,@PRECARRIAGEBY,@PLA CEOFRECEIPT,@VESSEL_FLIGHTNO,@PORTOFLOADING,@PORTO FDISCHARGE,@FINALDESTINATION,@TERMSOFDELVIERYNPAYM ENT,@DISCOUNTLABEL,@DISCOUNTRATE,@DISCOUNTAMOUNT,@ INVOICETOTAL,@AMOUNTINWORDS,@LCNO,@REMARKS,@INVOIC ELABEL)

DECLARE @INVOICEID CHAR(6)
SELECT @INVOICEID = MAX(INVOICEID) FROM INVOICEMASTER
/*@INVOICEID = (SELECT * FROM INVOICERETURN WHERE INVDATE=@INVOICEDATE AND INVNO=@INVOICENO AND INVTOTAL=@INVOICETOTAL)*/



INSERT INTO INVOICECHILD1(INVOICEREF,MARKSANDCONTAINERSNO,NUMB EROFPKGS,DESCRIPTIONOFGOODS,THICKNESS,COLOUR,SELEC TION,SIZE,UOM,CURRENCYDESC)
VALUES (@INVOICEID,@MARKSANDCONTAINERSNO,@NUMBEROFPKGS,@D ESCRIPTIONOFGOODS,@THICKNESS,@COLOUR,@SELECTION,@S IZE,@UOM,@CURRENCYDESC)
COMMIT TRANSACTION
GO

The problem with above query is some data type conversion exist.. what exactly is that,i cant find out??

Any help would ease my development work!!!

Thanks in Advance..