Hi, there is one more step you can try to see if it works.
On your iPhone and choose Settings, iCloud on your iPhone.1. Turn off Text Messages (or ensure it is turned off). I know this sounds counter intuitive but stay with it.2. You'll see a pop-up. Select: 'Keep on My iPhone'.3. Now turn back on text messages.4. Tap 'Merge', and wait. After a few minutes the deleted text messages should appear back on your iPhone.
If that does not work, then the messages are no longer available
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