After Botox, I get a large dent/hollow/wrinkle above my eyebrows. Approx how much filler would be needed to fix this?

I love the eyebrow lift, but it’s not worth it in exchange for these weird dents. My forehead looks uneven. I’ve been to 2 experienced doctors who had different (seemingly balanced) placements and get them every time. I’m afraid that adding more Botox there will decrease the lift, so I’m wondering if filler is a better option. What type of filler would be best and how many syringes? Sorry for the picture. The odd auto-cropping prevented me from only showing my forehead!