Why can't I answer calls on my Moto Z?

[Android Central Question]

Up until recently (a month ago approximately), when I received a call on my Moto Z (the modular phone from Motorola), I could simply swipe up on the green button to answer. Now, I hear the ring (or vibrate), have to unlock my phone, go to the phone app, select go to cal in progress, and then answer. Why is this happening, and more importantly, how to I go back to the previous method.
BTW, I have a friend with the exact same phone and exact same problem.

 

[B. Diddy]

Welcome to Android Central! Does this also happen in Safe Mode? https://support.motorola.com/uk/en/solution/MS113768