Care should be taken (1) to ensure that the overtime was approved, preferably in advance, and (2) that the amount and type of overtime (regular or irregular), credit hours, and compensatory time is accurately recorded.
Care shouldn't be taken to ensure that the overtime was approved.
mnli hypothesis: Care shouldn't be taken to ensure that the overtime was approved. premise: Care should be taken (1) to ensure that the overtime was approved, preferably in advance, and (2) that the amount and type of overtime (regular or irregular), credit hours, and compensatory time is accurately recorded.