I am sorry to hear of your wife's issue with her text messages on her device. I know it can be very frustrating. If she does the auto delete inbox on her device it would delete the oldest messages that she has once the box is full. She can lock her messages that she would like to keep. We do suggest that she do a factory reset on her device. This will set the device back to the factory settings like when she got the device out of the box. You can follow these steps to do so http://vz.to/1ygudJp. I am confident that this will resolve this issue.
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