Thanks for that information @user8ZJ0sqjXzw Your phone appears to be running up to date however I do see that AT&T recently pushed an update out for your Gear. For more information and instructions on how to update your gear, please check out their site: https://www.att.com/devicehowto/tutorial.html#!/stepbystep/id/stepbystep_KM1147956?make=Samsung&mode...
Hi,if messages always can't be deleted ,I suggest you use an Samsung Eraser.
But it is more troublesome than deleting it directly on your phone.
You need download it on youe computer and connect your device to computer,then the program will scan your files ,and you can choose delete your messages.