It happens just this afternoon,around 4:31 AM. The recent happening before that happen is that I accidently subscribe to GOUNLI5 instead of GOUNLI50 (which frustrates me a lot) after which, the message pops out which reads that it deducted my load because I have a maintaining balance. So I subscribe to GOUNLI20. My boyfriend texted on me and I replied. It sends. But after I send my second message to him, the dialog box said [Message Cannot Send. Phone Number Formatted Incorrectly]. I don't know why. I didn't change my bf's number in 4 months. This is the first time I encountered this problem. My signal is okay though.