Used s7 edge, screen burn

[sea_change]

I purchased a used S7 Edge. I've had the phone for one week now. I am noticing that the screen has a pinkish "ghosting" of the keyboard on it. There is the same colored ghosting on the top half of the screen, but I cannot tell what it is.
This ghosting can be seen in any app or page that has a light background. I believe it is screen burn, but it can't be from anything I've done.
I haven't used any single screen or keyboard option long enough, plus I have my screen set to turn off after one minute.
What can I do? Does the 90 day warranty that came with the used phone cover replacing it because of screen burn?

[jeffc]

Hey there, @sea_change! Really sorry about the situation. We'd love to help you.  Please send us a private message for further assistance. 

[sea_change]

Further assistance equals:
"Thank you. For Warranty coverage overview and claim process, we recommend you to call this number 844-834-5579. If you have any questions, please let us know."

Call the warranty claims, and they want me to send them the phone for them to look at, with no guarantee of fixing it, for an unspecified amount of time, with no replacement. So phone, plus all data (including sensitive data), goes off to warranty-land, and I am left phone-less in the interim. No bueno.
This solution may work for some, but I am not part of that some.
Shouldn't the solution be more like "Oh darn! Screen burn is not a problem we advertise as possible on our preowned phones! That's definitely beyond minor wear and scratches! We'll send out a replacement. Send us the bum phone back when you get the replacement!"