CocosCreator3.8.0 Playfab undefined?

I applied it like this after adding npm playfab sdk.
However, it is confirmed as undefined.
Teach me what the problem is

import { _decorator, Component, Node } from 'cc';
const { ccclass, property } = _decorator;
import { PlayFab,PlayFabClient } from 'playfab-sdk';

export class Test extends Component {

    protected onEnable(): void {
        if(PlayFab === undefined)
        console.log('?? undefined');

       PlayFab.settings.titleId = 'asda';

Which platform you are targeting ? If it’s correctly installed, at least you should be able to import it, or maybe it’s not initialized correctly, just guessing.
However, if you are targeting native platforms, you probably need to use Playfab native SDKs for Android, iOS or others. Some docs could be helpful