How to prevent strangers from writing private messages?

I don't know if the private message mentioned by the landlord refers to WeChat or QQ, if it is QQ. At present, private letters can't stop. In other words, if someone else's address book has your mobile phone or QQ number, you can add yourself.

But he just added you unilaterally. If you don't agree, you still can't establish a friend relationship, but he can send you some information under certain conditions.

Unless you block him or delete the same WeChat, you can receive his private message normally, unless you completely block him!