This buyer should have a mental illness
He would ask you to sell him the item at lower price （Normally unreadable low，the price he offered is basically consider "for free"）
Once you disagree with the price he offered, You will receive daily messages from him with most vicious curse and swearing.

We just checked，he did the same thing to other sellers
This is not a normal customer. When you see messages from him, you can choose to ignore it. It is recommended to block him to avoid placing orders at your store. Because if he places an order, he can open case on you for his own will, it will damage your interests. Like this scumbag, god knows what will he do.