If your PC is prompting for a BitLocker recovery key and only accepts numbers, it's likely that you are being asked to enter the recovery password, which is a 48-digit numeric code. This code is typically provided when you set up BitLocker or can be retrieved from a backup location where you saved the recovery key, such as a USB drive, printed document, or your Microsoft account if you saved it there.
Make sure you are entering the recovery password correctly, as it should only consist of numbers. If you have the recovery key saved in a different format (like a file or printed document), ensure you are using the correct numeric version of the key.
If you continue to have issues, you may need to check the BIOS or UEFI settings to ensure that USB drives are enabled for reading in the pre-boot environment, as this might affect your ability to access the recovery key stored on a USB drive.
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