I get a lot of text messages, but I can't return phone calls and text messages.

You can't forward this message, it comes from the information desk.

You receive this information for free, but when you forward it, you invisibly subscribe to some kind of monthly activity of theirs.

My PHS once received such a message, which was a joke and forwarded to a friend. I didn't care because the PHS list couldn't be adjusted. Later, when I was bored, I found that I had subscribed to this service for several months. I asked the receptionist for 6 yuan a month, and I didn't subscribe. He said I ordered it when I replied or forwarded it.