Wireless Joint

Apparently it's inordinately fond of https (which works too).
https://www.temblast.com/edl.htm

Usually everything these days is remote echo. So turn off local echo as you're only practicing typing. As stated, the screen does not stay up if you are not connected. So we can only presume that you're connected but have a dead session. Try just AT & Enter. Try ^D. Does anything make a differen...

Try both force off.
Line editing buffers the characters until a line is collected.
If you ever do get a response, then you can fine tune.