Baby not drinking much milk

Melissa
My little girl peyton isn't drinking a lot of milk lately last few days I've had to trying and force her to drink even 30 ml of it in the day 
She wakes up for one feed in the night and she has about 120ml then but threw out the day she will try and spit it out or start whinging and crying cuz she doesn't want it 
Any advice ?? It this normal for a 7 going on 8 month old 
She's my first baby so not sure when things stop and start 
She eats jar food in the day and has porridge for breakfast and suppers