CREATE TRIGGER [dbo].[TgrLog] ON [dbo].[tblLotAssign]
FOR UPDATE, INSERT
select * from inserted
How would you get
@LotAssignNo,@SerialNo,@LotName,@tlaid,@LotID,@status,@assigndt,@ToppingDate,@RackingDat parameters in trigger.
You could use below to identify to get the values
SELECT * FROM INSERTED
SELECT * FROM DELETED
If record exist in both Inserted and deleted table then its a update, and if only exists in inserted then Insert and Only in deleted then its a Delete.
Based on that you can use a flag identifier also to check that what was the action performed on you table.