Ketone count

Hi All, I know there are different ways to check if you are in ketosis. Could I ask what everyone uses to check it and why?

I used the urine strips but now that I am fat adapted they show just trace? I read that apparently this can happen when your body is efficient at using ketones for energy.

Need to consider a new way of checking.

In addition, does anyone use a cgm? Mine after fat adapted shows higher level of glucose in the blood... is this normal? In the start i was super low and then it went up to 5.5 mmol....I am definitely under 20g in my carbs so I am.wondering why this high all the time.

Thank you!