Call to undefined function bzdecompress PHP

I have an Ubuntu 16.04 server with PHP7 + nginx running. I already have a project in PHP Laravel 5.1 running in my local enviroment (Windows with Xampp) and everything is running great. I have a PHP script that uses the function bzdecompress of Bzip2 but then, in the server just crash and show this message:

Call to undefined function App\Http\Controllers\bzdecompress() 

I don't see instructions of how install this library (if needed) or how to load it or check at least that is loaded. Thank you very much!

via Chebli Mohamed