How to close the Pinduoduo pop-up window?

As far as the mobile phone model "OPPO-Reno5-Pro" is concerned,

You can turn off Pinduoduo's message notification in the phone settings, and then close the pop-up window.

1. Click to open the settings of OPPO mobile phone, as shown:

2. In the settings, select the notification and status bar, as shown:

3. In the notification and status bar, find Pinduoduo, as shown:

4. Slide left to close the message notification of Pinduoduo, as shown:

Then, you won't be informed about Pinduoduo on your mobile phone.