Did you increase or start working out at the same time you started IF. Or did you increase the amount and intensity of that activity? How many calories are you in deficit on average a day? What you are seeing isn’t really a plateau more then you haven’t lost any. So that isn’t like it worked and then slowed down/stopped. That simply might be because you aren’t actually in a deficit or that you have reconfiguration happening. So weight on a scale is only one part of the change. Adding muscle and losing fat could mean you basically don’t show a loss as 6 weeks is a fairly short time. You say your measurements are not much changed. If they have that is something. While not massive that could be part of that. Again you are a fairly low weight to begin with so all of that can be going on b ut you are not really seeing any change on the scale.
Lift weights. Do less cardio. Drink water. Get restful sleep. Be patient.
Definitely look at any junk calories you’re consuming like sodas. Add in fruits and veggies to meals.
Your starting weight is not very high although I don’t know your height. The fewer pounds to lose, the longer it takes, in general. I would not cut out food groups, I would definitely not do anything that feels unsustainable or like a starvation diet.
You can do this.