If your counts and expenditures are correct, then I think your calorie deficit is too large and your body has gone into starvation mode. It messes with your metabolism to protect fat reserves.

Fat cells do fill up with water before shrinking, but 8 weeks is a long time to maintain a calorie deficit that should drop 2-3 lbs per week and only drop 4.

Try no or minimal calorie deficit for a week and then try to keep your defict around 500 calories and adjust from there. You will probably want to keep it less than 1000 calories if you're still looking at wanting significant weight loss. The human body can be really efficient when it needs to be, but there is a price to be paid.

IANAD, so this is just me spouting advice I had been given in the past.