Random single or groups of three MMS texts are sent to me from a few of my friends, but the texts were not from them. I find out when I receive a notification: "Unable to download messages." I am using the default Messages app. I looked around on Google and my issue seems like the Stagefright exploit back in 2015, but is patched out now. What can I do to make sure I did not download one of the suspicious MMS texts? How can I prevent them from appearing from my contact list?