I purchased a Tapo C402 with solar panel, connected it to 2.4G network, but then realized I cannot see it from outside of my house.

I have tried everything: reseted the camera, reinstalled it, reseted the router (Zyxel)...and problem was not solved.

 
Please help me!!!

By the way: I have another two cameras (Tapo 530WS) connected to the same network, and they work perfectly and can be seen from anywhere.