I've checked my connection and it says that it is good. My phone and my roku are on the same network. I see Apple Airplay and Homekit on my roku, and airplay is on and it requires code "first time only". Screeen mirroring mode is set to "prompt" and there are no blocked devices. I'm able to connect my roku express 4k to the roku app.
When I try to airplay from my iphone (ios15.2), the roku does not show up on my phone's airplay or screen mirroring menu. Other devices, such as my appletv or my computer, do show up in that menu. I've tried screen mirroring and airplaying, but it doesn't show up in my phone's list of options to choose from. I've tried with my roommates' phones as well and none of them see my roku, but they do see other devices.