現状

SDカードが認識されているものの、I/Oエラーが発生しており、データの救出が難しい状況

time fsck -p /dev/sdb1
fsck from util-linux 2.39.3
fsck.fat 4.2 (2021-01-31)
There are differences between boot sector and its backup.
This is mostly harmless. Differences: (offset:original/backup)
  65:01/00
  Not automatically fixing this.
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