Tom, you’re right.
I contacted my hosting and the operator told me to switch 777.
I was able to connect once then after 5 mins it’s gone.
I call them again, they told me that was their mistake because the specs of the host which I purchased did not support this kind of connection. (unless I upgrade the product.)
The suddenly connection was operated by their NEW staff and they apologized for that.
Now I understand that if I pay more to upgrade the host then I can obtain more functions.
Well, I’ll just leave it and calculate my pocket to think about that.
At least, they bring me 5 mins happiness. Ha Ha
Anyway thanks for your help.