Not completely sure how you got that maintenance calories. I’ve just ran your numbers on a first one that google came up with and approximate BMR was under 3k cals. But that should still put you in a deficit.
If you eat carbs in the non-fasting time, the weight and especially water will fluctuate. 1 week isn’t long enough to actually measure the fat loss (by weighing). So keep at it and weigh at the same time, under same circumstances (right after waking up and going to the toilet, the same day - e.g. sunday morning).