The error “Download failed because you may not have purchased this app” typically occurs when the game or application is unable to verify the necessary files, often due to incorrect file placement or incomplete downloads. Here are the detailed steps to resolve this issue:

### Step-by-Step Instructions

#### 1. Check File Placement
– Ensure that the OBB (Opaque Binary Blob) file is correctly placed in the game’s directory.
– If you downloaded the OBB file, it should be placed in the Android/obb directory of your device. For example, if the game is com.example.game, the OBB file should be in Android/obb/com.example.game.
– If the OBB file is not in the correct directory, move it there by locating the downloaded OBB file, long pressing on it, selecting “Copy” or “Cut,” navigating to the Android/obb directory, and pasting the OBB file into the correct directory.

#### 2. Verify Download Completeness
– Ensure that all necessary files, including the APK and OBB, have been downloaded and are present in their respective directories.
– If you’re using a mod or additional files, ensure they are also correctly placed and named according to the game’s requirements.

#### 3. Clear Cache and Data
– Clear the cache and data of the game from your device’s settings by going to Settings, navigating to Apps, finding the game, selecting it, and pressing Clear Cache and Clear Data. Restart the game to see if the issue is resolved.

#### 4. Force Stop and Restart
– Force stop the game from your device’s settings by going to Settings, navigating to Apps, finding the game, selecting it, and pressing Force Stop. Restart the game to see if it loads correctly.

#### 5. Wait for Rollout Completion
– In some cases, the issue might be related to a rollout process. If you’re experiencing this issue with a specific game, try waiting for at least 4 hours after confirming and starting the rollout.

### Additional Tips

– Update Everything: Ensure that your device and all apps are updated to the latest versions. Sometimes, outdated versions can cause compatibility issues.
– Check for Black Screen: If the game opens but shows a black screen, it might indicate that the game is trying to load resources but failing. In this case, deleting the game data and reinstalling it can help.

By following these steps, you should be able to resolve the “Download failed because you may not have purchased this app” error and successfully download and play your game.