baby formula, whole milk & juice?

It seems by 11 month old baby has more or less completely gone off her formula milk. She had been having 3 x 8 oz bottles a day (that she actually drinks from beakers) with juice inbetween. But she’s hardly drinking at all now. She’ll have a few sips at meal times and a bit durring the day, but its hardly anything compared to what she did use to drink. I have tried water, different flavour juices, whole milk, adding flavlours to milk and she’s just not interested. Her soft spot on her head isnt really recessed or anything, so she’s not dehydrated, plus she still has wet nappies, but how can I encourage her to drink more? I have been using beakers with the spouts, She hasnt got the jist of how to suck through a straw, but is comfortable drinking out of cup. Any suggestions as to what to try? Is there any reason why she isnt drinking as much? Any help or advice appreciated.

Oh and she is eating 3 meals a day – breakfast, dinner and lunch. Also snacks on biscuits and fruit durring the day aswell and has a pudding after her main meal.