When you say
flickering, do you mean the screen is flashing black with every page turn? If that's the case, then perhaps your kindle is set to refresh the screen every page turn. See the beginning of this post:
https://www.mobileread.com/forums/sho...d.php?t=152104
E-ink displays need to be refreshed at least every couple or few pages to prevent ghosting.
If not, describe the flickering in more detail. You might want to call Kindle customer service.