Hi,
Try to go to SPM and apply the license for this hardware key and use the correct component.
Is the standby server up and running .
Run the command to get the hardware key and then add another license for that one .
You cant apply the license for the standby node as the system is not running on it. So when it comes up there you can apply it as i don't know the setup of the landscape.
181543 - License key for high availability environment
1619879 - licensing of HA/DR/cluster -> invalid license
Thanks
Rishi Abrol