I am trying to do import but there is no 'column header' option to select for time
why? how to resolve?
It looks like the issue is that you've got the first row set as the header line whereas the file uses the second row. This can be altered in your mapping import when selecting the file, like so:
As you can see here, I've set the 'Header Row' to 2.
Hope this helps resolve.
While the solution is provided by @AdamCookson, there is one more step before you change the import headers and data number. Delete the existing import and import data source for that action and do re import and select the header number and first data row correctly.
Edit: you can also edit the existing Import data source.