Whats wrong with my phone and can I fix it?

[???]

I have a Cricket Samsung Messager II and I have had it since June. Now almost every time I get a text message and I press the button to reply, the screen turns white. If I lean the phone to a side, I can barely see part of what the text says. The screen goes back to normal when I turn the phone off and turn it back on, but then it turns white almost every time when I go to reply to a text. Any ideas of what could be wrong and how I could fix it? Thanks in advance.