Please keep in mind that if you do incorporate weights into your routine, you will likely see the number on the scale rise, as muscle weighs more than fat.
I put on over one stone after using weights for approx two years before I stopped. I was, of course, much physically stronger, I also looked bigger in my arms, glutes, and thighs and have never been able to lose the muscle so still weigh significantly more than I ever did. For some, this is a huge positive. For others not, it's very personal.
I never personally noticed weight loss from having more muscle, I know that's what it says online, but it wasn't the case for me. I was also incredibly hungry due to growing new muscle mass.
The only exercise I've ever noticed helps me lose weight is lots of long walking, but I think this is mostly water loss.
I think you may be over exercising, your cortisol could be high, which encourages the body to hold onto fat.
For the calories, burned exercise actually increases appetite, making it harder to stay within calorie deficits.
You need to be in a deficit, I'd occasionally go above maintenance to stop your body from adjusting to the lower calories.
Exercise has benefits, but not necessarily weight loss.
I wish you luck xx