Build a DocumentReference to the document you want to update, then use the update() method on the DocumentReference to indicate only the fields to be added or changed . Pass it an object with only properties that match the fields to add or change.
How do I add a field to an existing document in firestore?
Build a DocumentReference to the document you want to update, then use the update() method on the DocumentReference to indicate only the fields to be added or changed . Pass it an object with only properties that match the fields to add or change.