Yes, this is a well-known issue; you should have seen it if you searched for it.
Amazon will usually send replacements over this. However, it may take you four or more Kindles to get one that doesn't fade in the sunlight. You might ask if it's possible to have your replacement be a new one rather than a refurb if you have to exchange it again.
Why it happens with some and not others is unknown to me. It seems most probably a UV problem, which would suggest some screens should have some UV protection coating and some screens not. But that's just a guess.