Try to use an interface (contract) name instead of class name:

$this->app->bind(MyApiContract::class, function(){
    return new MyApiClass(env(‘API_KEY’), env(‘API_KEY’));
});

Of course, you can use the interface to force your class to implement the required method:

class MyApiClass implements MyApiContract {
    //…
}

class MyOtherCustomApiClass implements MyApiContract {
    //…
}