Help! Lightroom super underexposed all images!

I've been out shooting all morning, with my Mavic Air 2 in some fantastic foggy weather. I've got back uploaded the files to my mac and they look great, both JPEG and DNG I've then gone to upload the DNG files to Lightroom and its super underexposed all of them to the point where there is literally no detail.

I've tried raising the exposure but it just makes the image so grainy and unusable now, any idea whats happened here?

Below i've attached the same file in lightroom and on mac preview for reference