unable to retrieve text messages

This is the first I have heard of this (and I work with iPhone text-message data every day!)

Here are my first thoughts:

• As AmishCake suggested before, did you close all of the apps (or really, just the Messages app) and then restart the device. (And not the other order? I just want to be sure we try that first.)
• Have you tried opening the messages app from a text-message notification (so it goes directly to the conversation with the new message?) I'd like to experiment with a message from someone other than the person who sent you a bunch of images, just in case the crash is from rendering that conversation on the screen.

There's some more heavy-handed things we can do (like backup, factory restore, restore from backup,) but I prefer to start with some simple poking around before we get crazy 😉

Close all open apps by double-tapping the home button, then swiping up and off the screen with the app window (not the smaller icon).

Reset your device: hold down the home button along with the sleep/wake button until the screen goes black and you see the Apple, then let go. (No data loss)

Generally, if you connect the iPhone to a power source and WLAN at the same time with the screen locked, the iPhone will automatically back up the data on the phone to iCloud.

If you have iCloud backup enabled, the iTunes backup will be disabled.

Thus, in this situation, you have to use a third-party SMS recovery software to get deleted iPhone text messages back by directly scanning the data on the phone even you don’t have any backup. Among tens of iOS data recovery apps, it is the only one that allows you to transfer the recovered messages back to iPhone.