I apologize for using all caps, but that is what my phone keeps telling me. The first few times that I saw it, I was afraid how my phone determined "unwanted" text messages, but since my inbox fills quickly, I have seen this message many, many times.
Unfortunately, I have not seen it every time, because it often pops up while I am using my phone, and it seems to accept any key as approval, instead of only "OK", which would actually make sense.
Then it deletes all of my unread messages, including ones that I have not had the opportunity to read.
I do not know what the OS is called, Wikipedia does not name it, and it looks the same as the one I had on my ZTE.
That, unfortunately, was absolute garbage!
Most basic phones have very little internal memory, so you won't be able to save many messages. I would start by getting an SD card, if you don't already have one in your phone, and saving everything you can to it -- including photos, videos and ringtones -- to free up some memory.
If this problem persists after deleting all unwanted text messages, you may want to do a factory reset on your phone and start with a clean slate. A reset will delete all your data, so make sure your photos are saved to your SD card and backed up to your computer. If you use Backup Assistant, back up your contacts; otherwise, you'll have to key them all back in.
Xist, I understand that it would be upsetting for text messages to delete on their own. One thing I would suggest is turning on auto delete to prevent the whole inbox from being erased when this pops up. Auto delete actually deletes older messages one at a time as space is needed. This way, all of your messages aren't erased at once and you don't have to remember to erase messages every so often. You can still lock messages that you want to keep. To turn this setting on, go to Messages, press Settings, Auto Erase Inbox, turn on.
Let me know if you need further assistance.
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