Homekit

Hi all, thank you in advance for taking the time to read this... I've added a smart bulb to my Hallway. Named the room and its on my iPad as a hub, it automatically synched with my older iPhone 8, and shows up on that phones Home Screen as a room, same with my MacBook Pro, but my new iPhone 13 mini shows its there if I open "edit settings" but it isn't appearing on my home kit home page as a room. If I try to add a room I just get a message saying "this room already exists". All my devices are set up to synch through iCloud. But the room (Hallway) just isn't appearing on the HomeKit Home Screen. Even though the phone is recognising it as been there and I can operate the "Hallway" with Siri on my iPhone mini.