If the game has a decompression failure problem, please try this method:
Open: C:\Program Files (x86)\Steam\steamapps\common\Mount & Blade II Bannerlord\Modules\Native\AssetPackages folder.
The error message should have the name of a file with the file extension “.tpac”.
Locate and delete the file in the AssetPackages folder.
Verify the game files through Steam and try launching again.