Index Column Doesn't Increment

I am using Ignition 7.6. I have created a new table in MSSQL database for charting. I have setup a Historical Transaction Group and added the SQL tags that I want. It is executed and running but the Index Column is recording null values. All other data is recording in to the database.

I would guess that when you created the database you did not specify the index column to auto increment.

This is done within SQL Server.