need help! going back to stock bootloader

Hi all, i was going to root my phone five months ago but i never finished i just unlocked the bootloader and changed the twrp recovery. ive searched all over the site for a stock image to go back to since, i failed to save mine. i really just want to do the ota that ive been putting off for five months if anyone can help me and maybe tell me how to exactly go about this that would be great!!!

its m8 H/K
(bootloader) version: 0.5
(bootloader) version-bootloader: 3.16.0.0000
(bootloader) version-baseband: 1.05.20.0321_2
(bootloader) version-cpld: None
(bootloader) version-microp: None
(bootloader) version-main:
(bootloader) version-misc: PVT SHIP S-ON

(bootloader) imei2: Not Support
(bootloader) meid: 99000499174239
(bootloader) product: m8_whl
(bootloader) platform: hTCBmsm8974
(bootloader) modelid: 0P6B70000
(bootloader) cidnum: SPCS_004
(bootloader) battery-status: good
(bootloader) battery-voltage: 0mV
(bootloader) partition-layout: Generic
(bootloader) security: on
(bootloader) build-mode: SHIP
(bootloader) boot-mode: FASTBOOT
(bootloader) commitno-bootloader: ab0efa49
(bootloader) hbootpreupdate: 11
(bootloader) gencheckpt: 0

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