Missing text message history

Hey people,

I just got the new iPhone 11 3 weeks ago (October 10th) and previously had an iphone 7. I did an icloud backup from my old phone to my new phone and there were no problems. Then a week later, I noticed my text history from September 22nd to October 18th is missing. I also noticed my text history with some of my contacts were also missing. I have been to the AT&T store twice and I have been to the Apple store twice. I have reset my phone to factory settings and completed backups manually from my computer as well as from icloud and I am still having the same issues (missing text history with contacts and missing month of text history). I am not missing photos, music, notes, etc. Just text messages. AND my messages continue to update in my old iPhone 7 so I know these messages are in the **** cloud somewhere. I don't know what else to do. I am close to returning my iPhone 11 and just going back to my iPhone 7. Any icloud geniuses out there who can help?