Access to network resources through an external IP, being in the same network?

Question

Mikrotik

Greetings colleagues!
Help solve the problem:
There is an Internet with a dedicated ip, for example, 31.31.31.31 connects to the Mikrotik 1 router, a dhcp server with an internal ip 192.168.1.1-254 is raised on the router, then Mikrotik 2 is connected to it via optics with the assigned ip 192.168.1.2, on Mikrotik 2 also raised a dhcp server with a mesh 192.168.88.1-254, cameras with ip 192.168.88.64,65,66 are connected to Mikrotik 2
For clarity, the scheme:

I need to access the camera via an external IP to connect to it through a mobile application on the phone .
I make the following settings to forward the camera to the Internet. On mikrotik 1 I forward port 8000 to 192.168.88.64 it looks like this:

add action=dst-nat chain=dstnat dst-port=8000 in-interface=ether1 protocol=tcp to-addresses=192.168.88.64 to-ports=8000

Next, I specify the route to the grid 192.168.88.1-253. Like this:

add distance=1 dst-address=192.168.88.0/24 gateway=192.168.1.2

What happens: being on the 4G Internet on a mobile phone, I can connect to the camera and watch it via an external IP, but as soon as I connect my phone to wi-fi Mikrotik 2, access stops. Still being in the mikrotik 2 network and entering ip 31.31.31.31 in the browser, I go to the mikrotik 1 admin panel. Something is missing in the settings ... which is not clear ...
Colleagues, help me figure it out!

Answer 1

Just solved this problem last week.
Only I had a port: 99, but the essence does not change

Answer 2

the passphrase is nat loopback.