The best suggestion I have to to direct the error rows to another table where that column is varchar, rather than a datetime type, and see if there's bad/badly formatted data.
Or try changing the datetime2 columns to varchar and see if the import works. If it succeeds, then try a SELECT query like this:
SELECT * FROM obj_test
WHERE TRY_CONVERT(datetime2(7), obs_sdate) IS NULL
OR TRY_CONVERT(datetime2(7), obs_edate) IS NULL
If that DOESN'T return any rows/bad data, then I'm at a loss.