Can I fix a whiting out screen?

In April, I received an LG441G as part of TracFone's 2G network shutdown replacement offer. Last week, without apparent cause (dropping the phone, etc.), some white horizontal lines appeared near the top of the screen; there don't appear to be many or any more lines like that, but it's hard to tell. The problem has worsened through the screen getting too bright to read, inconsistently. Sometimes it's mostly clear when the phone is turned on, other times it's completely white and dims later. Sometimes it flickers, though I'm not sure it's doing that any more. Everything else on the phone seems to work fine still, as far as I can tell, and the screen does still go to sleep.

I looked on iFixt soon after discovering the problem, but, finding that there was no entry for this device, I wrote LG. LG told me to talk to TracFone. TracFone apparently doesn't have an email address, just a link claiming to lead to one, so I called them. They said that they only offer a replacement, not a repair, and that I'd have to call from another phone to get it set up (which I don't have and would have to borrow somewhere). That seems quite a bit of bother for what may well just be a loose connector, and so here I am.

Any ideas? I'm hesitant to just go poking around inside without knowing what I'm doing, since, if I do have to get it replaced, I'd like to take advantage of the warranty.