I have a Net10 pre-paid phone and it continues to send random text's at random times to a 1121611611 number. How I know this is because I will get a text message saying, 13284950148 Error invalid number. Please re-send using a valid 10 digit mobile number or a valid short code. -S- and then a bunch of other letters and numbers follow. The number I've underlined a moment ago changes a little bit each time, same amount of digits just a little different sequence of numbers.