If the player won and the Credit request failed, the RGS will retry this Credit transaction until success, so these requests must be idempotent on the Operator side. It means if several of the same Credit requests come, the response must be with the same result and should not contain the error of duplicated transaction ID.
If the Cancel request failed, the RGS will retry this Cancel transaction until success, so on the Operator side must be idempotent processing.
If the player won some game feature (freespin, respin, etc.) that requires additional action, and the game interrupts (for example, due to connection loss, device discharged, or the game was closed by the player), then the game state is saved and will be restored the next time the player enters the game. This means that round can be started and finished in different sessions. There can also be a wide time range between a start and an end.