i am using the stock texting app. so i guess that is normal for android phones....good to know i am not the only one.
It's not the phone it's the network. I've seen this happen with a variety of phones (android, IOS, Windows) on a variety of carriers. And it's generally seen by users who activate their phones in ANYTHING outside of the actual carrier stores. The reason I've been given is you're between cell towers and it confuses the phone, and it periodically continues as time goes on.
The only way I've seen it permanently fixed was to take the phone FULLY off the network, reboot (factory reset), then put the phone back on the network. Depending on the carrier you can do this at home or in the carrier's store. I've seen other methods tried, and sometimes they work, sometimes they don't. I will say that when you walk into the carrier's store, the problem often instantly stops. So you may not want to walk in there with the intent of showing them