no text alerts on replies

I have recently purchased iphone 11 pro max transferring everything to it from my old iPhone 7. The only problem I have is that when I have sent a text message I do not get an alert when a reply is returned. I have tried all the suggestions in apple support and non have worked. I have checked all the settings both in notifications and messages and the phone is not on silent. I onloy know I have a reply is when I physically open the message app. Help!!