Hi,
I'd be happy to help you out with your question. Sorry for the inconvenience caused.
There are a few reasons why this could be happening. Please refer to below cause and solutions:
Activation limit reached: Each Windows 11 Pro retail license has a limit of one activation at a time. If the license is already activated on one machine, it cannot be activated on another until it is deactivated from the first machine. To deactivate it, you can use the "slmgr /upk" command or reset the machine to its default state.
Azure AD connection: The Azure AD connection may be causing issues with the license activation. Try disconnecting the first machine from the Azure AD domain before deactivating the license key and activating it on the second machine.
Phone activation: If the phone activation option is not working, you can try contacting Microsoft support. They may be able to provide you with a confirmation ID for activation.
License type: Make sure that the license key you purchased is a retail license and not an OEM or volume license. These license types have different activation rules and may not be transferable.
Time delay: Sometimes, there can be a delay between deactivating a license on one machine and being able to activate it on another. Wait a few hours and try again.
If you have any other questions or need assistance with anything, please don't hesitate to let me know. I'm here to help.
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