Why does my i-phone send me this text?

[IH1455UK]

My iPhone sometimes sends me texts that say "You have insufficient funds to send message" after my plan runs out when I haven't even tried to send any texts. Sometimes its just a single text, one time it was eleven in a row.

[gersong_vzw]

Ih1455uk, thanks for reaching out to us and I apologize for this inconvenience you are having with your device. I want to make sure you get the appropriate help to get this resolved and stop these messages from coming to your phone. Are you currently a Postpay or Prepay customer?

Gersong_VZW Follow us on Twitter @VZWSupport.

[kaebfly]

Prepay does it every time the devices attempts to connect back to the network. Happens on my youngest son's iPhone that is currently suspended (punishment). It's just something that it automatically does and doesn't really have anything to do with you attempting to send a text. My understanding is that the tower sees the connection attempt the phone makes and automatically sends that text.