Recent weight gain

Hi!

I've never posted here before, but I have a question that you all may be able to help me answer.

Over the last six years I've lost and kept off about 60 pounds. I weighed 190 at my highest and have averaged about 130 for the last year. Recently, I have gained about eight pounds. I'm still going to the gym and working out for about an hour to an hour and a half six days a week. I also eat pretty clean, but since I've hit this weight gain, I've been tracking very closely (Except for veggies, I rarely measure those ounce for ounce). Prior to this week, I've only consumed 1,000-1,300 calories a day on average. I'm not crazy hungry in general.

Workouts include strength training and cardio, of varying routines each day, and at least 30 minutes of cardio.

My total TDEE is 2155, and now I'm tracking to the ounce everything that I eat, and I'm consuming 1400 calories and burning off 300-400 in exercise. My macro breakdown is 40% protein, 40% carbs and 20% fat! though it sometimes runs closer to 50% protein and 30% carbs. 90% of those carbs come from veggie and legumes. Some from dairy, though I mostly use low or non fat dairy to help get my protein numbers where I need them to be.

Can anyone think of why I have gained weight? I've never gained before in my weight loss, so this is stressing me out. Any thoughts?

Body fat percentage right now (per calipers) is 25%, and I'm trying to get that down.