low to no ketostix readings

I’ve been doing the ketogenic way for apprx. 5 months.At the start I maintained a pretty good level of of ketosis on my ‘Ketostix”…In this period I went from 186 LB.s to 161 LB.s. As I got to my lower level of weight my “Ketostix” are not showing any sign of ketosis. Ive increased my fat to see if I could get back on track ….I wonder if my portions are out of whack….My fat grams are usually about 70…Protein are usually about 100 grams…Carbs are always below 15… and get plenty of sleep and am stress free.

Do you think I could still be in Ketosis but not show it?

Thanks for your time and help.

TommyBee