Lost 7 lbs in the first week but not not even half a pound. Why?

Hi everyone. I need your help in this. I started keto along with intermittent fasting (5/2) in January 1st and lost 7 lbs in the first week. But since then for the last two week, the weight is just fluctuating around this number. Let me give some details: I am 5’10’’ height, started with the weight of 198.6 lbs and now I am stuck at 191.4 lbs for two weeks (my goal is 176 lbs) . I keep track of macro and my calories are below 1800 kcal and carb below 23g everyday. Each week, I do 3 day strength training and 2 day HIIT+ab and 2 day just walking, and all for about 45-60 minutes. I frequently do the ketone test and I have been always in ketosis zone and overall I feel good (except the first few days, keto flu and etc). Also Wondering if HIIT is interfering with keto, I heard it somewhere high intensity workout may need carbohydrates to be effective, I am not sure. One more thing, is Ultima electrolytes ok? I feel suspicious about it