Arlo wired doorbell can’t alert all authorities IPhone while press the button

[Genta7126]

I just buy Arlo essential wired door bell, and I have already installed it. All my family use IPhone. The mobile phone account authorized to the family has been opened, and the camera can be seen, but when someone presses the doorbell button, the phone notification is still only the one that was originally set. What is the problem?