Hi there, firstly if baby is not drinking anymore then don't give it to baby anymore. No matter fm or bm, u have to finish it within the hour otherwise the contents are spoiling the longer u drag. Just feed baby a smaller feed more often. Some babies are small drinkers . Let them dink what they want, if they are hungry they will cry for the milk. Pls don't force, u will only force all the way growing up and what the point of having unhappy feeding time so many times a day?
It is absolutely normal that babies want to look around. They will soon want to sit up and look around. Then are u going to force again? U can coax a few times but if don't want then don't want already. Babies are humans, sometimes they like to drink more sometimes they like to drink less. If 120 is not working out then just make 90 or 60.
If u want, u can try and see if changing to a medium flow teat works out. Sometimes it could be a teat issue and this u will only know. If u try it. But if still the same, then it is not a teat issue then.
Talk to the baby when feeding. Shake the teat or move the mouth a little.