While linking your Angry Birds 2 save data is generally a smooth process, users may encounter issues along the way. Here are some common problems and their solutions:

Playing as a "Guest" might be fine for a quick level, but it stores your data locally on your device. If you delete the app or get a new phone, that data is gone forever. By linking your account to a third-party service, your progress is stored on the cloud, allowing you to pick up exactly where you left off on almost any platform. How to Link Your Account (Step-by-Step)

Once your account is linked, restoring your data is straightforward: Install on your new device.