Advice for babies feeding

My little girl is 8, nearly 9 months old and she is still waking up every 2 hours for a feed, my health visitor says it’s normal but I’m exhausted by it. Just lately it feels like she isn’t getting enough milk at night time and I was wondering if that’s why she is waking up so often because she isn’t getting enough at each feed. I still want to continue breastfeeding but can I top her up with a bottle of formula during the night so my partner can feed her one of the night feeds? I don’t seem to pump enough milk whilst exclusively breastfeeding her all day/night. Any advice appreciated