How to fix overallocation warnings

Hi

I found a thread on here from a few years ago, offering a solution to the problem of overallocation warnings when using Disk Utility's first aid on an APFS container. The solution suggested the following...

1) Create a bootable clone on an external drive, I used Carbon Copy Cloner and a Samsung T5.

2) Boot from the clone (press and hold the option key before power-up to get the boot menu)

3) Run ** first aid on the internal APFS container -> expand detail view

4) Scroll detail view up to find the path and name of the drive. In my case, it was /dev/disk0s2

5) Open Terminal

6) Enter sudo fsck_apfs -y -o /dev/disk0s2

The command will check all volumes of the container and then fix the overallocation

at the end of the procedure:

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I followed these steps, but entering sudo fsck_apfs -y -o /dev/disk0s2 into Terminal instead gives this:

fsck_apfs: invalid option -- o

usage: fsck_apfs [-q | -n | -y] [-l] device

       -l            live fsck (lock down for verify-only)

       -q            quick check if the superblock and checkpoint superblock are valid.

       -y            always repair (answer "yes" to questions)

       -n            verify only (answer "no" to questions)

Can anyone offer an explanation of the above or how to proceed?

Huge thanks to anyone who replies!

J