Hi @Amanda3, let me see if I can help out here!
Have you tried clearing data for the messages app? This will not delete any previously sent or received messages, but it will reset all settings for the app which might do the trick. Find and tap Settings > Apps & notifications > Show all XX apps > Messages > Storage > Clear data > Tap "OK" > Restart the phone.
Another thing that you can try is to reboot your phone in safe mode to see if you are able to receive text messages there. Safe mode is a troubleshooting mode where all apps downloaded from Play Store is temporarily deactivate, that way you can see if this behaviour is caused by a downloaded app. For more information on safe mode and how to use it, click here.
Try these measures and feel free to keep me posted with the results!
