HELP with feeding

We're having issues with Emma's feeding - or lack of appetite really.
She weighs 5kg so is suppoesed to have anywhere between 600-900ml of milk in 24 hours. Well, we barely get to 500ml every day - she's on EBM 100% BTW. We have tried everything we can think of - forcing her to eat doesn't work as she gags easily and ends up thorwing up. Dream feeding her doesn't work as she refuses to drink or gags on the milk. Waking her up more often to feed doesn't work as she's too sleepy and cries until she's left alone to sleep. We have tried feeding feeding her twice - once when she wakes and then before she goes down for a nap but she normally refuses to take the bottle.
I'm really struggling with this so any advice will be appreciated. TIA

Is she gaining weight OK? If so, I wouldn't be too worried as it means she is getting enough, gremlins would never take the "recommended" amount of formula but they gained weight nicely so it was never an issue. The problems came later when their weight gained stopped.

Chiara is quite a sleepy feeder so we strip her down to feed her, and if she still won't wake I stroke her face with a cold, wet face cloth just to annoy her enough that she stays awake. I know what you mean about gagging on it tho, when she is out to it nothing can make her take a feed, and when I tried a bottle of EBM at my midwife's recommendation coz she thought we could get it into her in her sleep she just refused to open her mouth and the milk all ran down her face.

No she's not gaining weight very well at all - has slowed down in the last 6-8 weeks and I fear it's only getting worse
Deb, I have tried feeding stright from source but she refuses to take the breast even when hungry. Like Eden, she won't take the milk unless she's ready for it and that's not very often
I wonder if it could be her gums giving her grief? She's been trying to chew on the bottle teat and is dribbling like mad
I am going to try the teat next size up and see what happens - our GP recomended we did that when Gina refused to drink and it worked for us