To have a better understanding on the situation, may I ask how did you originally obtain the Windows license, and are you trying to reactivate it on the same PC or after a hardware change? Also, please share the exact activation status shown under Settings > System > Activation, along with whether you use Windows 11 Home or Pro.
Digital licenses normally do not provide a separate product key, so these details will help determine the correct activation method.
Hope to hear from you soon