Connection issue on facetime and share play

When I test "remote control" function on iOS 18 beta, I use two iPhones and connect them via FaceTime. But when I tried to share screen, if one iPhone sends a request for “ask for share”, the other iPhone will not receive the request. Screen sharing can only be successful when one phone "share my screen". But even so, after successfully sharing the screen, when clicking the "remote control" button, neither phone responds.