My screen wont work when its on something white!

I dropped my phone it has been cracked but i have used it with no problems until lately it started blacking out and i noticed the screen is still sometimes on unless its on something white like when i scroll down i cant see it at all but if i connected it through my laptop and changed to a black theme i can see the screen just fine. It appears to be something to do with the part of the screen that controls white. Because when i had it on something white it wouldn't be black or very very dim. This happened after i reset the phone. If someone could help me it would be much appreciated! Thanks.