How do I prevent iPhone from listening

I’m being driven a bit mad by my new iPhone!

I have gone into settings and done the following:

Settings - Keyboard - turned off dictation

Settings - Privacy - apps. None have access to the microphone

Settings - Siri and Search - turned off Siri

The blue mic icon is still blue at the top right of my screen.

When I hit the mic key in the keyboard it asks if I want to enable dictation, so defo disabled, but still listening.

When I am trying to add a photo caption, or typing a query in Safari, Bing, Edge, iMessage, literally every app with text input, it is putting in any speech around me. Weather from radio in car (as passenger!), TV, husband and I talking together as I type - in goes everything that’s being said. It’s taking me ages to do anything as this thing keeps putting in all the background blather. Having to turn off radio/TV, tell no one to talk around me, and not talk when typing (had to just remove the stuff it put in from me talking to the cat!) is infuriating.

Please, please can someone tell me how to kill this unwanted functionality?

Thank you!