Sounds/Notifications

I had an iPhone XR which would only play sounds when I receive texts/WhatsApp messages occasionally. It sometimes plays just a ping and sometimes the sound that it is set to play in settings. It pings on my Apple Watch and vibrates but will only occasionally make an alert sound as it should on my phone.

I have gone through all the settings I can think of and been into my local Vodafone shop. My Ring doorbell also only works occasionally.

I decided to buy a new iPhone 11 but the new phone is exactly the same. Last night it played a sound on my phone when I activated my doorbell but today nothing. One text I received sounded the correct alert others nothing.

could it be something to do with my Apple Watch I wonder. Would appreciate any advice/help.