Introducing formula (and bottles) at 6 mos... need all the advice!!

My girl is 6 months old and EBF since birth. She cannot tolerate dairy so I've cut all from my diet and that alone has been really hard and stressful. I've thought about supplementing with formula so I can have at least have cheat days as the milk protein only stays in your breast milk for so long before it's clear again. Or simply for when I accidentally have dairy as I have zero milk stash. I just don't have the time to pump. On top of this I'm now thinking of introducing it because I feel my supply might be dropping, not entirely sure but it just seems like it. My concern is anytime we have tried to give her bottles she's refused them. She took a few at the beginning but since then we just haven't offered them enough. Does anyone have any advice on how to navigate this? Anyone have any experience with this issue? Thanks in advance! ❤️