Since iOS 18.03.02, sound notification not working on messages or WhatsApp

My iPhone 13 has been fine until last update of iOS 18.3.2 . Alerts of MESSAGES by sound no longer work. I had the same problem with WhatsApp but managed to fix that. I have tried all advice I’ve found on google and this site (not for this update but iOS 17++) Can anyone help please?

PS WhatsApp is now not giving a sound alert again and I’ve done nothing!

Please can you help, I’m missing messages that need immediate attention.