If you don't see the above you need to go to Apple and ask why. However, this is how you can answer a call so you must not have understood me.
That is because your phone is locked when the call comes in. Have someone test this for you by calling you when the phone is not locked. There is no need for a decline button when the phone is locked.This is what my screen shows when I get a call:
![]()
Press the Power button twice quickly.I beg to differ, but obviously there is a need if I am asking about it in the first place. The need is to get the phone to stop ringing.