Why does jsapi 2.6.2 introduce index.js and it still says that my DingTalkPC is undefined?

DingTalkPC.config({

agentId: '', //Required, micro application ID

corpId: '',//Required, enterprise ID

timeStamp: '', // Required, generate the timestamp of the signature

nonceStr: '', // Required, generate the random string of the signature

< p> signature: '', // Required, signature

jsApiList: ['device.notification.alert', 'device.notification.confirm'] // Required, jsapi list that needs to be used< /p>

});

js has been introduced, why does it still say that my DingTalkPC is undefined? Has anyone encountered the same problem?