X_LEDGER_POSTING_CONFLICT
Means
a ledger posting key is already stored with other entries
Typical cause
the key was posted before and this posting differs in its line count or in a line, so writing the new lines beside the stored ones would leave the book unbalanced
Fix
entries: [ … the posting as first stored … ] — in the enqueue of the ledger job — or a new key (e.g. '<key>:adjust-1') for a correcting posting