Water damage to the touch screen

I had a lifeproof case on my phone which didn't seem to work to well because I ended up getting water inside it. But anyway, shortly after, my phone screen would turn purple and only purple. Then it would slowly fade to black. So I put it in rice overnight and the phone would turn back on and all of the colors were back to normal. The only problem is that the touch screen doesn't work. Everything lights up and is fine, I just can't press any of the touch screen buttons. It's completely unresponsive. I NEED HELP