T-SQL Transaction and rollback

ALTER PROCEDURE [dbo].[usp_ATFT_FIN_setTransactionsPaid] 
	-- Add the parameters for the stored procedure here
	@companyID				INT
	,@accountparentID		INT
	,@accountsubID			INT
	,@checkvalue			DECIMAL(18,2)
	,@strInvoiceIDs			VARCHAR(100)
	,@description			VARCHAR(250)
	,@documentID			INT
	,@TransactionNumber		INT
	,@TransactionDate		DATETIME
AS
 
SET NOCOUNT ON;	
BEGIN TRANSACTION 
 
DECLARE @err INT 
SET @err = @@ERROR
 
		-- insert bank account debit transaction
		INSERT INTO
			dbo.tbl_FIN_Transaction 
				(							
				companyID
				,ClientID
				,TransactionNumber
				,TransactionName
				,TransactionDate
				,AccountParentNumber
				,AccountSubNumber
				,DocumentID
				,DocumentType
				,Debit	
				,Credit
				) 
			VALUES
				(													
				@companyID
				,0
				,@TransactionNumber
				,@description
				,@TransactionDate
				,@AccountParentID
				,@AccountSubID
				,@DocumentID
				,'JNL'
				,@checkvalue	
				,0
				)
 
	-- insert individual A/R transactions per invoice
	-- set invoices to isPaid = 1
	-- comma separated string with invoiceID's
	DECLARE @values TABLE (id INT) 
    DECLARE @id INT 
    INSERT INTO @values (id ) SELECT VALUE FROM ufn_ParmsToList(@strInvoiceIDs) 
    WHILE @@rowcount > 0 
    BEGIN 
      SELECT TOP 1 @id = id FROM @values 
      IF @@rowcount > 0 
      BEGIN 
            EXEC usp_ATFT_FIN_setInvoicesPaid @id ,@TransactionNumber,@description, @accountsubID, @checkvalue, @companyID
      END 
      DELETE @values WHERE id = @id 
    END
 
IF @err <> 0 
	BEGIN
		ROLLBACK TRANSACTION 
	END
 
SELECT @err AS intError
COMMIT TRANSACTION