Android has two sorts of data placements. Here is how you go with it.
When you are supposed to place the data files in the Android/obb , it means you cannot download the data directly from the game. The game needs to verify the license from Google Play.
When the data is supposed to be placed in the Android/data folder, there is no issue of license verification involved. You can download the game data directly from the game.
Now, in your case, the obb file may have issues. Check if you have placed it in the correct folder. Check for the information on the data file from the site you downloaded it. Check the the correct naming of the file so that the game can identify it and access it. If the naming is incorrect, your game may fail to identify the data file and return the stated error.
Go to your Application Manager, select the desired game and clear data. Now place the data file in Android/obb.
If it doesn't work, try downloading the game and the associated data files from some other sites. There could be some issues with your data file.
However, please note that it is always harmful to download games and the data from third party sites.They carry the risk of having mal ware or viruses. It is always advisable to download the games from official store or from reliable sources only. If, however, you need to download a game or an app from such sites, make sure you scan the files before installing.
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