Disk utility shows error

When I perform first aid on my Macintosh HD I get the following output

Verifying file system.

Volume could not be unmounted.

Using live mode.

Performing fsck_apfs -n -l -x /dev/rdisk1s1

Checking volume.

Checking the container superblock.

Checking the EFI jumpstart record.

Checking the space manager.

Checking the object map.

Checking the APFS volume superblock.

Checking the object map.

Checking the fsroot tree.

error: btn:1: invalid key order (8) oid 79632 / oxid 11317

fsroot tree is invalid.

The volume /dev/rdisk1s1 could not be verified completely.

File system check exit code is 0.

Restoring the original state found as mounted.

Vorgang erfolgreich.

How can I fix this?