error ios app wifi and mobile network

I checked the MFCM iOS archive on the phone when downloading the network error. When you are connected to Wi-Fi and run the function, it works normally. I turned off Wi-Fi and confirmed that when I ran the function with the mobile network, it returned an Exceiption that I was not connected to the network.

where do i have to search the problem with this app on Xcode?

error ios app wifi and mobile network
 
 
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