HELP guys

I have a question.
Sorry for my bad English.

I have Zosi nvr cameras and till 3 days ago all worked fine.

But now i cant see the cameras when im outside my local wifi.
So not with 4g and also not with external wifi.

You should think its a router problem butttt,

The factory in China did make a test and they can see it with 4g. They sent me a picture of my frontdoor.

So i dont understand it anymore.