Rooted Kindle Fire HD 8.9 8.5.1 and now it's stuck on FastBoot mode screen?

I'm trying to turn this tablet into a pure android tablet but after rooting I'm stuck on the fastbook mode screen.

I can find the tablet in device manager under some strange gibberish and under file explorer under USB_device.

I've tried: rebooting, rebooting with volume up, rebooting with volume down, unrooting which says it cannot find device (used same I used to root it).

At this point I'd just like to either pure android it OR get it back to being a kindle.

Help!
Added (1). when it boots it shows the kindlefire logo for a second then red screen then "fastbboot mode' and stays there.

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