partitioning – EFI Partition not taking up full space

You have increased the allocation for the EFI partition,
but you have not resized the file-system in the partition.
This is why Disk Management reports 598 MB, while fsutil still
reports the old value of 96 MB.

To correctly resize the partition, you need to resize it from a
bootable USB media using a third-party product that will resize
both the partition and its file-system.

Ensure you have good backups before doing any partition editing.

For more information see the post
How to enlarge Windows 10 EFI partition.

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