The cancelled booking you must never send.

Where a retry sweep goes wrong

A homeowner confirms an appointment and cancels it thirty-two seconds later, before the conversion has gone out. A retry sweep looking for "confirmed, never sent" then finds that booking and tells Meta about an appointment that no longer exists. It goes on telling it every time the sweep runs.

Why it matters more than the request

Both platforms learn from what you tell them. A conversion event is not a report; it is a training label. Send one for a cancelled appointment and the bidding is now looking for more people like the one who cancelled. If the whole point of sending a booking event instead of a form fill is to buy people who show up, a cancelled booking is the single worst label you can attach.

The rule

• Only the state now matters. A lead that confirmed, cancelled and rebooked stands confirmed again, and you owe it a conversion, because an appointment exists. A lead that confirmed and cancelled gets nothing, however many confirmed events its history holds.
• Put the rule in the query that finds what to send, not in the sender. The sweep's query has to check the state too. If only the sender does, the sweep keeps selecting the row, calling the sender, and hearing no. That reads like a failing platform.
• Count one conversion per appointment, dated at the first confirmation. A booking moved twice has three confirmed events and is one conversion. The first one marks when it happened, and the platform already holds it under that id.

The same rule on Google

An offline conversion import keys on the click id and the conversion time. The state check is the same: do not upload a booking that no longer stands. Google does not know about the cancellation unless you also use conversion adjustments, and most setups do not.

What this does not cover

• Whether to send a retraction for a booking the homeowner cancelled after the conversion landed. Meta has no clean way to do this; Google has adjustments. That is a separate decision.
• No-shows. A booking that stood and went unkept differs from a cancellation. The honest treatment is the same either way: send the deeper event only when the visit happened.