Hi Guang, I have tried as per your instructions. Here's the outcome but my office is still showing Activation required. I have followed the video as well. Please help!
Microsoft Windows [Version 10.0.17134.112]
(c) 2018 Microsoft Corporation. All rights reserved.
C:\WINDOWS\system32>cscript "%ProgramFiles%\Microsoft Office\Office16\ospp.vbs" /dstatus
Microsoft (R) Windows Script Host Version 5.812
Copyright (C) Microsoft Corporation. All rights reserved.
---Processing--------------------------
PRODUCT ID: 00202-20949-57997-AA991
SKU ID: 95820f84-6e8c-4d22-b2ce-54953e9911bc
LICENSE NAME: Office 16, Office16O365HomePremR_SubTrial5 edition
LICENSE DESCRIPTION: Office 16, TIMEBASED_SUB channel
LICENSE STATUS: ---LICENSED---
ERROR CODE: 0x4004FC04 (for information purposes only as the status is licensed)
ERROR DESCRIPTION: The Software Licensing Service reported that the application is running within the timebased validity period.
REMAINING GRACE: 30 days (43367 minute(s) before expiring)
Last 5 characters of installed product key: 8FDW8
PRODUCT ID: 00339-10000-00000-AA590
SKU ID: d450596f-894d-49e0-966a-fd39ed4c4c64
LICENSE NAME: Office 16, Office16ProPlusVL_KMS_Client edition
LICENSE DESCRIPTION: Office 16, VOLUME_KMSCLIENT channel
LICENSE STATUS: ---OOB_GRACE---
ERROR CODE: 0x4004F00C
ERROR DESCRIPTION: The Software Licensing Service reported that the application is running within the valid grace period.
REMAINING GRACE: 29 days (41835 minute(s) before expiring)
Last 5 characters of installed product key: WFG99
Activation Type Configuration: ALL
DNS auto-discovery: KMS name not available
KMS machine registry override defined: kms7.msguides.com:1688
Activation Interval: 120 minutes
Renewal Interval: 10080 minutes
KMS host caching: Disabled
PRODUCT ID: 00200-70000-00000-AA543
SKU ID: d7279dd0-e175-49fe-a623-8fc2fc00afc4
LICENSE NAME: Office 16, Office16O365HomePremR_Grace edition
LICENSE DESCRIPTION: Office 16, RETAIL(Grace) channel
LICENSE STATUS: ---NOTIFICATIONS---
ERROR CODE: 0xC004F009
ERROR DESCRIPTION: The Software Licensing Service reported that the grace period expired.
Last 5 characters of installed product key: KHGM9
---Exiting-----------------------------
C:\WINDOWS\system32>cd %ProgramFiles%\Microsoft Office\Office16&cscript //nologo ospp.vbs /sethst:kms8.msguides.com >nul&cscript //nologo ospp.vbs /act
---Processing--------------------------
Installed product key detected - attempting to activate the following product:
SKU ID: 95820f84-6e8c-4d22-b2ce-54953e9911bc
LICENSE NAME: Office 16, Office16O365HomePremR_SubTrial5 edition
LICENSE DESCRIPTION: Office 16, TIMEBASED_SUB channel
Last 5 characters of installed product key: 8FDW8
<Product activation successful>
Installed product key detected - attempting to activate the following product:
SKU ID: d450596f-894d-49e0-966a-fd39ed4c4c64
LICENSE NAME: Office 16, Office16ProPlusVL_KMS_Client edition
LICENSE DESCRIPTION: Office 16, VOLUME_KMSCLIENT channel
Last 5 characters of installed product key: WFG99
<Product activation successful>
Installed product key detected - attempting to activate the following product:
SKU ID: d7279dd0-e175-49fe-a623-8fc2fc00afc4
LICENSE NAME: Office 16, Office16O365HomePremR_Grace edition
LICENSE DESCRIPTION: Office 16, RETAIL(Grace) channel
Last 5 characters of installed product key: KHGM9
ERROR CODE: 0xC004F017
ERROR DESCRIPTION: The Software Licensing Service reported that the license is not installed.
---Exiting-----------------------------
C:\Program Files\Microsoft Office\Office16>