If your keyboard isn't working and you can only input numbers, you may have difficulty entering letters for the BitLocker recovery key. Unfortunately, there are no specific instructions in the provided context regarding alternative input methods for letters when the keyboard is malfunctioning. However, you might consider using an on-screen keyboard if it's available in the recovery environment. This would allow you to click on the letters using your mouse or touch input.
If the on-screen keyboard is not accessible, you may need to troubleshoot your keyboard issue or use a different keyboard to input the recovery key correctly.
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