7 months bottle refusal

For about two weeks our 7 mo has been refusing her bottle. She is exclusively FF. Every day is a battle while I try to get her to eat without creating an aversion. She does eat some solids, but the pediatrician told me she needs minimum 16 oz a day just for basic hydration. I believe she is teething, but no teeth yet. I feel like I have tried everything, I am out of ideas. She is home with her dad all weekend while I am at work and today she has only eaten 2 oz for him. I have tried

Sizing up nipple flow Changed formula Lights off, no noise/distraction room Added non alcoholic vanilla to make it tasty Introduced various cups

To me, this seems to be a behavioral problem, not mechanical/physiological. For her motn feed when she is sleepy, she will drain 6 oz in 5 min. Any suggestions? Did this happen to you and your baby just… got over it?