Hi @Saurabh Mittal? , thank you for reaching out.
It seems your final table structure is expecting the 4 columns because the first time when you created the table it set up column structure. In order to remove the above error, you have to drop the table. This can be achieved in the publishing action of Manual settings page.
Click on the edit in Publishing action:
Set the Output dataset to the Drop table every run
This will create a new table with the latest table structure. You can revert the settings once the new table is created with the same name.
Hope this helps.
Best,
Apeksha Prasad