Information about obtaining activation codes can be found in the digital support section. Look here: http://gameflydigital.custhelp.com/app/answers/detail/a_id/318/kw

Otherwise, contact the GameFly digital support team:

Digital Support: (For PC Games & the Digital Client)
• Monday-Friday: 9:00 AM to 12:00 AM Midnight Central Time
• Saturday-Sunday: 9:00 AM to 10:00 PM Central Time
• digitalsupport@gamefly.com or http://gameflydigital.custhelp.com/app/ask
• Virtual Agent: 24 Hours http://gameflydigital.custhelp.com & click "Ask Ryan"