My objective of keto diet is initially lose at least 40 lb - Dr. Berg's Healthy Keto

My objective of keto diet is initially lose at least 40 lb and eventually adopt it as a life style. So far I am diappointed with my progress. I have lost ONLY 20 lb in 10 months !!! This is my daily meal plan: 1- upon wake up coffee or green tea (no sugar or milk) 2- Around 4pm large meal of fatty lamb meat or chicken with skin or fatty fish sometimes with vegetables (Once a week I add rice) + large green leaves salad. 3- Around 8pm one cup of roasted either sun flower seeds or almond. Thank you