Mark a payment as one-time
Not every repeating charge is a subscription. When SSA gets it wrong, this action tells it to stop treating that particular pattern as one.
What the action does
Next to every detected subscription in the customer drawer is a Mark as one-time button, alongside Confirm as subscription (covered on how detection works). Use it when a repeating charge SSA grouped into a subscription was really a handful of separate, coincidentally similar payments.
Clicking it does three things in one step: the chain's payments are unlinked from the detected subscription and become ordinary charges again, a tombstone record is written remembering the customer, amount, currency and interval involved, and the detected subscription row itself is deleted.
What happens to the chain
Every payment that had been counted as part of the pattern is set back to a plain, unlinked charge. In Transactions they change from Recurring to Single payment, and none of them contribute to MRR, churn or retention any more. The subscription row is removed from the drawer entirely, not just hidden.
Remembered across syncs
Yes. The tombstone written when you mark a pattern as one-time is checked on every later sync, for the same customer and currency, at that amount within the usual 1% tolerance. A matching pattern is skipped rather than detected again, so this is a permanent decision for that specific price and customer, not something a re-sync will quietly undo.