I dont know which port to use

All devices are currently on same wifi network.

My app is connected to local server using port 9443. Server (on same wifi network) IP address “192.168.1.15”

On my esp i have written command blynk.config(auth, “192.168.1.15”, 8080) and auth is authorisation token I have genereated from the app.

EDIT
My phone is able to connect to the server as I am able to login to the blynk app. I believe that the ESP is not able to connect to the local server and that is why it is showing offline. So there must a problem either with the auth code or the blynk.config command. I have checked the auth code again. So that means there has to be a problem with blynk.config command more specifically IP Address or the port 8080. IP address is correct so essentially the problem is with 8080, right?