Sometimes the DRM fails if the servers are down. Try launching the game while your PC is offline.
When you encounter websites promising a simple .txt file containing valid license keys for FIFA 16, it is important to exercise extreme caution. In the modern era of digital rights management (DRM), activation codes are typically unique, one-time-use strings tied to a specific account. fifa 16 license key.txt download
Sites like CDKeys, Eneba, or Kinguin may still have "New Old Stock" digital codes. Be prepared to pay a premium, as these codes are becoming rare. Sometimes the DRM fails if the servers are down
If you play on PC (with a disc drive), Xbox, or PlayStation, buying a used physical copy is the most reliable method. The console versions do not require a "license key.txt" as the disc acts as the license. In the modern era of digital rights management