Parsing serial data from sim900 module esp32

Question

So lately I've been messing around with the idea of making my own cellphone nothing spectacular, just a basic one with touchscreen and basic functions call message calendar contacts list and the ability to connect to the internet and provide weather information via an api call.. The module Im using for gsm and GPRS communications is the popular sim900 module. I can communicate I can make calls I can do everything. But in stuck on a maybe (if not impossible to overcome) difficult roadblock.. You see sim900 module when receives a call transmits through the serial port the "RING" command followed by the "+CLIP.... (caller Id stuff)". OK I'm receiving that and I am breaking it down and accepting the command and all fine it works. But here comes the situation.. I want to read the battery capacity that is left (AT+CBC) and the gsm signal strength (AT+CSQ) all fine I'm sending those 2 commands at a fixed interval of like 3 seconds for the signal 10 for the battery. But now when a call comes it might overlap with the incoming response from trying to read the battery.. Let's say that I asked the module what is the battery level. Then the module will respond by sending "+CBC: (and battery level)" then let's say at the same exact time I receive a call.. Then all the data on the serial port just gets messed up and nothing is working.. My code is pretty rough and definitely the parsing section is awful but I'm more concerned that the parsing is not the problem. And the problem is the conflicting incoming data.. Is there any way of solving this problem? Or any other advice of where to look and how to approach the problem? Every command from the gsm is delimited by the 0D0A sequence (CRLF)

Bellow is an example code from what i am doing

//for parsing
String incomStr;
String FirstStr;
String SecondStr;
String ThirdStr;
String FourthStr;
String FifthStr;
String SixthStr;
int strcount;
char incomChar;
boolean flagz = false;


//parsing
void getIncomingCommand() {
  if (Gsm.available()) {
    incomChar = Gsm.read();
    //check to see if 0D0A if yes split the string 
    if ((incomChar == 0x0D) | flagz) {
      flagz = true;
      if (incomChar == 0x0A) {
        switch (strcount) {
          case 0:
            FirstStr = incomStr;
            incomStr = "";
            strcount++;
            flagz = false;
            break;
          case 1:
            SecondStr = incomStr;
            incomStr = "";
            strcount++;
            flagz = false;
            break;
          case 2:
            ThirdStr = incomStr;
            incomStr = "";
            strcount++;
            flagz = false;
            break;
          case 3:
            FourthStr = incomStr;
            incomStr = "";
            strcount++;
            flagz = false;
            break;
          case 4:
            FifthStr = incomStr;
            incomStr = "";
            strcount++;
            flagz = false;
            break;
          case 5:
            SixthStr = incomStr;
            incomStr = "";
            strcount++;
            flagz = false;
            break;
          default:
            strcount++;
            flagz = false;
            incomStr = "";
        }
      }
    } else {
      incomStr += incomChar;
    }
  }
}


void clearIncomingCommand() {
  FirstStr = "";
  SecondStr = "";
  ThirdStr = "";
  FourthStr = "";
  FifthStr = "";
  SixthStr = "";
  strcount = 0;
}


int getSignalLvl() {
  char tempchar;
  String tempstr;
  Gsm.print("AT+CSQ");
  Gsm.write(0x0D);
  Gsm.write(0x0A);
  delay(180);
  while (Gsm.available()) {
    tempchar = Gsm.read();
    tempstr += tempchar;
  }
  return tempstr.substring(16, tempstr.indexOf(",")).toInt();
}

String getTime() {
  char tempchar;
  String tempstr;
  Gsm.print("AT+CCLK?");
  Gsm.write(0x0D);
  Gsm.write(0x0A);
  delay(180);
  while (Gsm.available()) {
    tempchar = Gsm.read();
    tempstr += tempchar;
  }
  return tempstr.substring(tempstr.indexOf(",") + 1, tempstr.lastIndexOf(":"));
}

void setup() {
  //start serial port
  Serial.begin(115200);
  //start the gsm port
  Gsm.begin(9600, SERIAL_8N1, 32, 33);
  strcount = 0;
  updateTime(getTime());
  delay(200);
  updateSignal(getSignalLvl());
}

void loop() {
  //stuff inside here will only be called / run only every X amount of time
  // X = SECONDS/1000;
  if ((millis() - lastupdate) >= 60000) {
    updateTime(getTime());
    lastupdate = millis();
  }



  getIncomingCommand();
  if (SecondStr == "RING" & FourthStr.substring(0, 5) == "+CLIP") {
    Serial.print("SomeOne is calling!! Number: ");
    Serial.println(FourthStr.substring(8, 21));
      Serial.println(phoneNums[i]);
      Serial.println(FourthStr.substring(8, 21));
      callerPhone = FourthStr.substring(8, 21);
      clearIncomingCommand();
    //important change state only once!
    if (!change_state) {
      came_from = state ;
      change_state = 1;
    }
    Serial.print("coming from: ");
    Serial.println(came_from);
    state = 4;
    flag = 0;
  }
  else if (SecondStr == "NO CARRIER") {
    Serial.println("CALL ENDED");
    clearIncomingCommand();
    if (state == 3) {
      state = 5;
      flag = 0;
    } else if (state == 4) {
      state = came_from;
      flag = 0;
    }
    change_state = 0;
  }
  else if (SecondStr == "MO RING") {
    Serial.println("CALLING...");
    clearIncomingCommand();

  }
  else if (SecondStr == "MO CONNECTED") {
    Serial.println("CALL CONNECTED");
    clearIncomingCommand();
    if (state == 2) {
      state = 3;
      flag = 0;
    }
  } else if (FourthStr == "OK" | ThirdStr == "OK") {
    Serial.println("Recieved ok clearing buffers");
    clearIncomingCommand();

  }


}