Firebase not uploading

The code doesn't upload on firebase at all
also the esp8266 is connected to wifi

Firebase.begin(FIREBASE_HOST,FIREBASE_AUTH);
the underline word "Firebase" is not highlighted orange could it be a problem ?

#include <FirebaseESP8266.h>


#include "./esppl_functions.h"

#define WIFI_SSID "Sonson"
#define WIFI_PASSWORD "hassan13"

#define FIREBASE_HOST "https://friend-detector-e9036.firebaseio.com/"
#define FIREBASE_AUTH "1AAjJuU7CbSXu2P90GvChDCRGi58I3fdmtWELhW6"

FirebaseData firebaseData;

#define LIST_SIZE 7

uint8_t friendmac[LIST_SIZE][ESPPL_MAC_LEN] = {
   {0x08, 0xc5, 0xe1, 0xb1, 0xec, 0x43}
  ,{0xc8, 0x3d, 0xd4, 0xf8, 0x41, 0x2b}
  ,{0x80, 0x01, 0x84, 0x14, 0xf5, 0x0f}
  ,{0xec, 0xf3, 0x42, 0x35, 0x7c, 0x40}
  ,{0xc4, 0x3a, 0xbe, 0xa4, 0x0c, 0xa0}
  ,{0xc0, 0x17, 0x4d, 0xd3, 0xd8, 0x0f}
  ,{0x20, 0x47, 0xda, 0x3d, 0x69, 0x3b}
  };

String friendname[LIST_SIZE] = {
   "note9"
  ,"lap"
  , "Said"
  , "Nada"
  , "Aya"
  , "khaled"
  , "Sohaila"
  };

bool frienddetected[] = {false, false,false,false,false};

void setup() { 
  delay(500);
  
   Serial.begin(115200);
   Serial.println("Started...");
   WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
    Serial.print("connecting");
    while (WiFi.status() != WL_CONNECTED) {
    Serial.print(".");
    delay(500);
    Firebase.begin(FIREBASE_HOST,FIREBASE_AUTH);
 
    }
    esppl_init(cb);
}

/* You cannot use a time delay here to keep the LED on, so will need to use ratio of 
detected packets to overall packets to keep LED on for longer. If you try to use a 
delay to keep the light on for long enough to be useful, the watchdog timer kills the 
process and it dies */
int cooldown = 0; /* This variable will be a cooldown timer to keep the LED on for longer, we'll set it to 1000 if we
detect a packet from a device with a MAC address on the list, and then keep the LED on till we get 1000 packets that 
are NOT from any device on the list. */
/* end exparimental variable package */

bool maccmp(uint8_t *mac1, uint8_t *mac2) {
  for (int i=0; i < ESPPL_MAC_LEN; i++) {
    if (mac1[i] != mac2[i]) {
      return false;
    }
  }
  return true;
}

void cb(esppl_frame_info *info) {
  for (int i=0; i<LIST_SIZE; i++) {
   if (( maccmp(info->sourceaddr, friendmac[i]) || maccmp(info->receiveraddr, friendmac[i])) && frienddetected[i] == false) {
      frienddetected[i] = true;
       Serial.printf("\n%s is here! :)", friendname[i].c_str());
       Firebase.setString(firebaseData,"/Attendance/0",friendname[i]);
      cooldown = 10; // here we set it to 1000 if we detect a packet that matches our list
    }}}

void loop() {
  esppl_sniffing_start();
  while (true) {
    for (int i = ESPPL_CHANNEL_MIN; i <= ESPPL_CHANNEL_MAX; i++ ) {
      esppl_set_channel(i);
      while (esppl_process_frames()) {
        //
      }
    }
  }  
}

Here is one problem I see:

param host - Your Firebase database project host without http:// or https:// protocol e.g. Your_ProjectID.firebaseio.com.

HassanBosha20:
the underline word "Firebase" is not highlighted orange could it be a problem ?

Not necessarily. Library authors must manually define the keywords of their libraries they want colored, and this is done very inconsistently. Some of them don't bother to define any keywords. Some of them define the keywords, but do it wrong, so they are not recognized by the Arduino IDE. Some of them only define a handful of the keywords. So don't put too much importance on the color of words in the Arduino IDE.