Xbox One external HD showing as full with nothing on it after a system update.

On Friday 16th June 2023 at 17:23, our Xbox One did a system update. When it was next used on Saturday the 17th June 2023, everything previously installed on the external hard drive was missing. However, the external hard drive is still visible to the xbox but showing as full 7.3TB. I've search online and seen similar comments about full external hard drives with nothing on them following an update but not how to resolve this.

:)