How do I wipe clean (for selling) a kindle e-reader. There is no option under settings. I have also held the power button for 20 seconds.
To factory reset your Kindle to wipe it clean of data:
From Home, tap the Menu (three dots) icon, and then tap
Device Options, and then tap
Reset Device. Your Kindle will restart.
Looking at the instructions, the key thing is to apply cleaning liquid to the cloth and then wipe the screen clean. Microfiber cloth is best. I use rubbing alcohol, but there is special cleaning fluid you can buy specifically for monitors and screens. Don't apply the liquid directly to the screen!
For older e-ink black and white screens on older Kindles, the screens were very touch-sensitive, and it was possible that you could damage the screens just by pressing down too hard. I'm pretty sure that screens now are tougher, but you should still use gentle wiping motions with the cloth.