Perform the MQTT connection during the setup

src/main.cpp

@@ -23,7 +23,7 @@ void setup() {
         Serial.println("ERROR: The config file could not be loaded");
 
     connect_wlan(config);
-
+    connect_mqtt(mqtt_client, config);
     initialize_sensor(sensor, error_code, error_msg);
 }
 

src/wlan.cpp

@@ -56,7 +56,6 @@ size_t construct_json(float *data, char *buffer, int buffer_size) {
 
 void mqtt_transfer(PubSubClient &client, Config *config, float *data) {
     char buffer[100];
-    connect_mqtt(client, config);
     size_t payload_size = construct_json(data, buffer, 100);
     client.publish(config->topic, buffer, payload_size);
     Serial.println("Data transferred successfully");