Baby refusing bottle and taking over a hour to feed.

LO is 6 months old currently still drinking 6oz formula at a time. I would say 20% of the time she will drink it all with no fuss but the other 80% is like going to war - she will constantly move around, try roll and grab anything near her, look at any little thing that moves and even spit out most of her bottle. It will take me over a hour sometimes trying to make sure she’s drinking her bottle, having to hold her up and wind her and re-heating the bottle 2-3 times nearly each feed because she won’t drink it cold.

Please someone help or give some advice on how to make this better. It’s not viable anymore and is wasting around 3-4 hours of our day just trying to feed her.