Both the C720 Floodlight Camera and the D230 Doorbell Camera work fine from my home, and I can access and operate them with no problems with the Tapo App on my mobile phone.  They are all connect via Wi-Fi and the signal is strong.

However, when I travel to another person's home, a club or airport and connect my phone to their Wi-Fi to view camera footage at my home, it does not work and the cameras will go offline.  Connecting through Mobile Data away from home does the same thing: the Tapo devices go offline.  When I arrive back at my house, the C720 is showing an amber LED.  I have to reboot the cameras to get them to work again.

Why are these cameras going offline when away from my home?