For the past couple years now, across multiple phones (S9, Pixel, OnePlus 8T), when I receive a call that I don't want to answer at the moment, and hit the red 'decline' button, the call prompt disappears for half a second, and then the phone keeps ringing. Obviously a serious bug somewhere along the line, as there isn't a legitimate reason for the behavior. As it's across multiple different phones, I must assume that it is on the network side.
We'll be more than happy to troubleshoot this issue as this action is performed by the device and not the network. When did this start? Are the devices software up to date?