How can i use my Windows Server 2016 Activation Key(CAL) for Windows Server 2012R2

[Aniket_Meshram]

I have a license key for Windows server 2016 But my OS is Windows Server 2012 R2 Standard, and I want to use that key to activate my Windows Server 2012 R2. Could anyone please let me know how can I convert it. 

Regards,
Aniket.

[#2]

You can contact the activation center to discuss downgrade rights and obtain the down level product key.

https://www.microsoft.com/en-us/licensing/existing-customer/activation-centers