Hi Sarah, have you shared your actual menus/food intake with some very rough in indication of quantities somewhere, in a diary, or on the menus thread at the top. Then we might be able to see if there is a problem somewhere. These can sneak up on you unaware - yoghurt with hidden sugars, prepared meats with hidden carbs, the list of potential pitfalls is endless...
If you know you have been 100% following the rules to the letter then don't give up, the loss will happen, mine always did in 5-7day spurts, in between my weight would stall or even go up!