WooPayments sometimes holds back part of a payout as a reserve and releases it on a later payout. The reserve isn't included in the transaction data WooPayments sends us, so those payouts can't balance on their own and show as Failed with "Settlement Data Discrepancy… please create an adjustment". Retrying won't fix it.
To fix it
On the Settlements page, click the Failed status on the payout. The Settlement Data Discrepancy window opens. Click Create Adjustment.
Choose Reserve Balance for a reserve held back or released, or Adjustment for anything else.
Check the amount against the "Fees and adjustments" line in the WooPayments payout email for that date.
Map Reserve Balance to a balance-sheet account, not an expense.
Your adjustment is kept if the payout is reprocessed.
If the difference doesn't match the payout email, or the payout failed for another reason (for example, orders not matched), email [email protected] with the payout date.