You can not. Once a system is activated, this activation cannot be removed because the license is stored in the Microsoft servers and not in the user's system. MS checks the hardware ID (HWID) and if a license is found in their database, the system will automatically activate.
O365 can not be activated with KMS. To activate it, the script installs Mondo 2016 licenses and activates it. This license is near to O365 feature-wise, you can get offline features of O365 but you can't get Online features of O365.
The online KMS option works for Windows 7 Pro & Enterprise (Not Ultimate). All Windows 8/8.1 editions are supported by Online KMS option.
-**Where can I donate?**\
MASSGRAVE project doesn't accept donations and it's free. \
It's because it's a community project and involves many contributors, splitting donations is not practical and also because profiting from piracy is not good.