We have a customer reported the following case and we would like to share it with anyone with a wireless camera:
I got the sim card last year and it was working. It suddenly stop working now. I have been working on this with the carrier and we have come to the conclusion that carrier keeps changing the type of service on the SIM card. They told me that their system automatically does what is called a "Sweeping Search" and there is no way to tell when it will happen. When it finds a device during the search that their system is unfamiliar with, it automatically changes it to a data service (which you would think would still send an email). They said I need to change the card to a Pre-Paid type to avoid the automatic sweep changes.