Problema con Private Mensage

[Snorlax01]

(Nombre de usuario) has chosen not to receive private messages or may not be allowed to receive private messages. Therefore you may not send your message to him/her.

If you are trying to send this message to multiple recipients, remove (Nombre de usuario) from the recipient list and send the message again.

Me sale esto al tratar de enviar mensajes a determinados usuarios.

Alguien me explica ???

NGD puede bloquear la recepcion de PM ???