Wap push message over http

Question

I want to send a wap push message which contains a URL to my android mobile & I want to see how it popups....

This is the URL I use.

It gives this error in my linux screen.

2019-01-28 13:25:15 [31965] [9] INFO: Box connection tried from denied host <172.16.20.77>, disconnected 2019-01-28 13:25:15 [31965] [9] ERROR: Failed to create new boxc connection.

What can I do? Any help is welcome!!!