I subscribed to a call forwarding service, ConXHub. When a call comes in, the app pops up a window with Accept/Reject buttons. That works fine. However, if I don’t press one of those buttons within about 2 seconds, that window disappears. I contacted ConXHub, and they told me their thousands of users have no problem with the app, and it must be an issue with my notifications. I’m running Pie on a Galaxy J7.