# 72007: LiveSync connector failed to track its position Identifier: `livesync_cannot_store_resume_token` A LiveSync MongoDB connector could not save its change-stream resume token to the database. The token records how far the connector has read, so that it can continue from the same point after a restart. ## What you should do Grant the connector's database user permission to read and write the `ably` collection, where the resume token is stored as a document. Without write access there, the connector cannot record how far it has read. ## Why it happens The MongoDB connector saves its change-stream resume token to a document in a collection named `ably`, and it could not write it. This is usually because the connection's database user lacks read and write permission on that collection. ## What you'll see The error is reported with code 72007 and HTTP status 500. The message is of the form `unable to store resume token: `.