location.sharing.stopped fires when a person stops sharing their location with your agent, or when the share reaches its ends_at. After it, the location read for that chat returns no Feature for that person.
Read the payload
Thedata object is the LocationSharingStoppedEvent schema from the API contract. The envelope around it is the same on every event and is described in the event catalog.
Handle the event
Stop reading the location fordata.chat_id and discard any position you keep for that person. A share that runs out fires this event within about a minute of ends_at.

