Answer to "Most of my text messages show (No Subject - Message size 1KB"I have had this problem pop up repeatedly (every month or two). I am not positive but I believe the problem is associated with using Facebook Messenger. Somehow FM either takes over for the phone’s original messaging solution or messes with the settings on which it relies. Many posts suggest the problem is associated with Hangouts app but I do not have that app installed on my phone, so it must be something else. So far, I have been able to solve the problem of No Subject texts by restarting my phone.