I have no idea why you are using an array?
Start using code tags when posting code, that keeps the indentation and hopefully you are using that?
When you are not sure of what you are doing, put the sql string/criteria whatever into a string variable and debug.print that until you get it correct. Then you can use that in your function/command whatever.
Then comment out the Debug.Print when you eventually get it working.
Code:
strSQL = "Insert into SampleITDataAll (YN, SetId) Values ('" & YN & "','" & SetId & "');"
Debug.Print strSQL
DoCmd.RunSQL strSQL
In fact as you cannot use Split() in a query, you need to create a wrapper function to split the data and return the required indexed data.
Then you could just use a simple query created in the Query design window.
Much easier in my view.