Supply has tanked, can I get 6m baby off formula??

Looking for some advice please. My baby is 6 months old and feeling has always been tricky. Thought she was tongue tied when she was really small and after the health visitor said that’s what it might be, took her to hospital and they said no it wasn’t. She feeds for such a small amount of time each side but recently it has dwindled to maybe 3-5 minutes if I’m lucky. I’ve had to start properly supplementing her with formula and honestly I’m absolutely heart broken.

Every feed feels like a bit of a battle - she latches on (though is pulling the boob /nipple outwards) and I’m constantly switching sides. My supply feels like it’s just tanked. The only time I feel like I have a chance with a feed is when it’s been a 3-4hour gap. If she’s hungry under that time it doesn’t work and I have to get a bottle as she gets too upset. I feel like I’ve failed her/my body is malfunctioning.

Is there any thing I can do at this point to pull it back and get my supply up? I fed my first baby for nearly 18 months and to feel like this 2nd journey is ending so soon is devastating.

Thanks in advance for any help.

TLDR- My milk supply is tanking and I’m having to supplement my 6 month old with formula. Is there any way to reverse this?