Any advice for the Aksha fight? :(

I'm confused about how strong Aksha's magical darkness is. I can't seem to do anything about it -- It makes the window lights and my light spells useless, and Aksha is immune to Shine, and she spams the magical darkness every time I lure her out of it. Also, the Daylight spell... the description seems to imply it is designed exactly for this kind of thing, yet when I cast daylight on her magical darkness nothing happens :/

I don't even know how many legendary resistances she has, because I've never managed to get her to use them all up -- the most I've gotten to in a fight is her using Legendary Resistance three times.

The moment she downs someone for the first time, I know the fight is basically lost, because it turns into whack-a-mole -- Whoever she downed is in the magical darkness every time because she cast it right on them, then whenever I try to get them back up she just whacks them back down. Since she has three legendary actions and there's only four of me, she ends up attacking five times a round (with advantage because of darkness), and when at least one of my people are down and other people are trying to get someone up, it leaves me with only two attacks per round (with disadvantage because of the darkness) against her five...

I always get to a point where she is still at full health from all her regens, and I am trying desperately not to die for round after round of somebody always being down.

I have Chill Touch on one of my casters, but just one round of him missing on his attack or having to do something else, and WHAM Aksha gets in 5 attacks and her regen on her turn which basically secure her back to full health.