Mqtt port issue . Not recognizing from config file.

[AlenSunnyMathew]

Environment
Here is the environment that I'm using':

Microconroller: . ESP8266
Core/runtime: [e.g. ESP8266 core for Arduino v3.0.2]
IDE: [Arduino IDE 1.8.19]
mqtt library: Adafruit_mqtt_client.h
Hai iam having the issues with the port. I have saved the mqtt configurations in SPIFFS and initialized with structure. When iam trying to connect with mqtt its failed. But its getting connected when the port number defined globally. Any thoughts?