8 month old and feedings

My 8 month old daughter will only drink 2 x 270ml bottles a day (one before a nap and bed). She will only drink them in her cot. If she’s not in her cot, she gets distracted way too easily and won’t drink.

She eats 3 meals a day on top of that. And I offer her water in a cup because that’s the only way she’ll drink water. She hates sippy cups.

I’m at a loss on what to do. Doctors aren’t worried because she’s gaining weight appropriately and has heaps of wet nappies.

Advice?