How to make remote answering through Bluetooth work
We want you to be able to answer your cell phone with just a single press of a button (the on/off button), but sometimes the iPhone will make you confirm you want to use Bluetooth every time. We don't want that, and this is how you fix it!
Head to the settings, then, Accessibility > Touch > Call Audio Routing > Bluetooth Headset
And that is it! We should be able to answer the calls with one swift press of a button!