Retrieve lost commit from GIthub [closed]

I have a very serious problem. Working in my repository have lost commits , and I need to return the repo to a specific commit .

It is a repository of a simple web that I was doing.

The API shows the commit that I want to return (see JSON below). I tried everything and there is no case.

link

"commits": [

    {
        "sha": "47af90bec132e9b4e0ac87efa720007e79682193",
        "author": {
            "email": "[email protected]",
            "name": "David Martín"
        },
        "message": "Ultimando detalles en JS. Finalizada",
        "distinct": true,
        "url": "https://api.github.com/repos/DavidRnR/WebEntrega/commits/47af90bec132e9b4e0ac87efa720007e79682193"
    }
]