There are a few reasons a game session may end unexpectedly:

• Inactivity timeout: Sessions automatically close after a period of inactivity. You will receive an on-screen warning before this happens. See the inactivity FAQ for more details.
• Game maintenance or update: Occasionally, a game may be temporarily taken offline for a required update. You will normally be notified before this happens. Simply try launching the game again once the maintenance window has passed.
• Unexpected crash: While rare, crashes can happen. Please try launching the game again — most sessions resume without issue. If the problem keeps occurring, contact our support team via live chat and let us know the game name and approximately how long into the session the crash occurred.