[Moto G6 Guides, News, & Discussion] who666:
UPDATE: somehow the problem fixed itself. Just follow the instructions from OP!

I'm trying to unlock the bootloader of my Moto G6 (XT1925-3, running OPS27.82-72) but, although following the instructions, I can't make it format and allow me to unlock it at the Allow OEM Unlock option in Android Settings > Developer Options.

A little more information about it: I'm trying to make it at a linux machine with adb and fastboot installed from apt. I can interact with it over abd and fastboot normally. Motorola already sent my unlock code for the ID I gave them (and double checked that it's correct) and the phone accepted it. I've made some factory resets before trying again. It gave me the following message after the first try:

...
(bootloader) WARNING: This command erases all user data.
(bootloader) Please re-run this command to continue.
OKAY [ 0.001s]
finished. total time: 0.001s

Submiting the same command again gave

...
(bootloader) Check 'Allow OEM Unlock' in Android Settings > Developer
(bootloader) Options
OKAY [ 0.001s]
finished. total time: 0.001s

Without delays or anything hinting that it formatted itself. After booting up the Allow OEM Unlock option is still grayed out. Any suggestions?

EDIT: when I type "fastboot getvar all" it returns

(bootloader) version: 0.5
(bootloader) version-bootloader: moto-sdm450-C3.0C
(bootloader) product: ali
(bootloader) board: ali
(bootloader) secure: yes
(bootloader) hwrev: PVT2
(bootloader) radio: 3
(bootloader) storage-type: emmc
(bootloader) emmc: 32GB SAMSUNG GX6BMB RV=08 PV=03 FV=0000000000000003
(bootloader) ram: 3GB SAMSUNG LP3 DIE=8Gb M5=01 M6=06 M7=00 M8=5F
(bootloader) cpu: SDM450
(bootloader) serialno: XXXXXXXX
(bootloader) cid: 0x0032
(bootloader) channelid: 0x09
(bootloader) uid: 5F5F2A1800000000000000000000
(bootloader) securestate: oem_locked
(bootloader) iswarrantyvoid: no
(bootloader) max-download-size: 534773760
(bootloader) reason: Volume down key pressed
(bootloader) imei: XXXXXXXXXXXXX
(bootloader) meid:
(bootloader) date: 07-27-2018
(bootloader) sku: XT1925-3
(bootloader) carrier_sku: XT1925-3
(bootloader) battid: XXXXXXXXXX
(bootloader) iccid:
(bootloader) cust_md5:
(bootloader) max-sparse-size: 268435456
(bootloader) current-time: "Thu Jan 1 0:35:46 UTC 1970"
(bootloader) ro.build.fingerprint[0]: motorola/ali/ali:8.0.0/OPS27.82-87
(bootloader) ro.build.fingerprint[1]: /108:user/release-keys
(bootloader) poweroffalarm: 0
(bootloader) ro.build.version.full[0]: Blur_Version.27.231.108.ali.retai
(bootloader) ro.build.version.full[1]: l.en.US
(bootloader) ro.build.version.qcom: LA.UM.6.6.r1-04400-89xx.0
(bootloader) version-baseband: M450_08.14.10.61R ALI_BRAZILDSDS_CUST
(bootloader) kernel.version[0]: Linux version 3.18.71-perf-g3ded56c (hud
(bootloader) kernel.version[1]: soncm@ilclbld35) (gcc version 4.9.x 2015
(bootloader) kernel.version[2]: 0123 (prerelease) (GCC) ) #1 SMP PREEMPT
(bootloader) kernel.version[3]: Mon Jul 16 15:07:10 CDT 2018
(bootloader) sbl1.git: git=MBM-NG-VC3.0C-0-g6a96fd0
(bootloader) rpm.git: git=02798db
(bootloader) tz.git: git=5fefee4-dirty
(bootloader) devcfg.git: git=5fefee4-dirty
(bootloader) keymaster.git: git=5fefee4
(bootloader) cmnlib.git: git=5fefee4
(bootloader) cmnlib64.git: git=5fefee4
(bootloader) prov.git: git=5fefee4-dirty
(bootloader) aboot.git: git=MBM-NG-VC3.0C-0-gce20f1a
(bootloader) frp-state: protected (144)
(bootloader) ro.carrier: tefbr
(bootloader) current-slot:
(bootloader) slot-suffixes: _a
(bootloader) slot-count: 1
(bootloader) slot-successful:_a: INVALID
(bootloader) slot-successful:_b: INVALID
(bootloader) slot-bootable:_a: INVALID
(bootloader) slot-bootable:_b: INVALID
(bootloader) slot-retry-count:_a: unknown
(bootloader) slot-retry-count:_b: unknown
all: listed above
finished. total time: 0.008s