Why does Tmall's pre-sales and after-sales customer service refuse to be added by others, so how should we talk to them?

Tmall's pre-sales and after-sales customer service refused to be added by others because they set it up, and then it was set up for security reasons. There are many people who consult every day, and some of them are advertising, so they are set up. You can double-click their heads to talk, or you can contact them and ask them to add you.