Not recognize in fastboot. Strange problem with back-lit?

[antleo]

So first problem: I wanted to update my recovery to a later one and was going to do it through fastboot. The phone boots to fastboot mode but the computer doesn't see it per se. It comes up in devices but not with the fastboot command.
Second my back light only seems to activate sometimes when I press the power button to wake up my screen.
Model is h811.

 

[SavageRobot]

Strange, so in adb you put
adb devices
and it sees the device there
adb reboot bootloader
and doesn't reboot? I assume if you can see it in devices you must have USB Debugging checked.
Is it not just easier just to update the TWRP actually in TWRP?

Are you on stock ROM? I think I had an issue with one of the old builds of ROM for my H815 where back light didn't register properly. Mine turned out to be the case, it had the gap for the light sensor at the front but for some reason wouldn't work. Hole must have not quite been big enough. If you have a case, try it without. If you don't take a look at ROM update if you are running non stock.

 

[antleo]

How do I update in twrp? And no, the phone will reboot to fastboot mode, and shows up in windows device manager as an Android device, but if I try any fastboot command I get waiting for device.