nodeMCU + Max30100 can't read BPM & SpO2

hello, this is my first post. I hope someone can help me fix this error in my project.
why, when I put Blynk.virtualWrite (V2, "Test") ; into my program, Max30100 cannot read BPM & SpO2 ? thank you

#include <Wire.h>
#include "MAX30100_PulseOximeter.h"
#define BLYNK_PRINT Serial
#include <Blynk.h>
#include <ESP8266WiFi.h>
#include <BlynkSimpleEsp8266.h>
#include "Wire.h" 
 
#define REPORTING_PERIOD_MS 1000

char auth[] = ""; 
char ssid[] = "";
char pass[] = "";
 
// Connections : SCL PIN - D1 , SDA PIN - D2 , INT PIN - D0
PulseOximeter pox;
 
float BPM, SpO2;
uint32_t tsLastReport = 0;
 
void onBeatDetected()
{
    Serial.println("Beat Detected!");   
}
 
void setup()
{
    Serial.begin(115200);
       
    pinMode(16, OUTPUT);
    Blynk.begin(auth, ssid, pass);
 
    Serial.print("Initializing Pulse Oximeter..");
 
    if (!pox.begin())
    {
         Serial.println("FAILED");
         for(;;);
    }
    else
    {
         Serial.println("SUCCESS");
         pox.setOnBeatDetectedCallback(onBeatDetected);
    }
 
    // The default current for the IR LED is 50mA and it could be changed by uncommenting the following line.
     //pox.setIRLedCurrent(MAX30100_LED_CURR_7_6MA);
 
}
 
void loop()
{
    pox.update();
    Blynk.run();
 
    BPM = pox.getHeartRate();
    SpO2 = pox.getSpO2();
     if (millis() - tsLastReport > REPORTING_PERIOD_MS)
    {
        Serial.print("Heart rate:");
        Serial.print(BPM);
        Serial.print(" bpm / SpO2:");
        Serial.print(SpO2);
        Serial.println(" %");
 
        Blynk.virtualWrite(V5, BPM);
        Blynk.virtualWrite(V4, SpO2);
        Blynk.virtualWrite(V2, "Test"); 
        
        
        tsLastReport = millis();
    }
}

This is because it should not be in the void loop. This loop should be running hundreds of times a second which will flood the blynk server by sending this info every loop. You will need to break this into functions that are called on staggered intervals. If you search “void loop clean” there are many examples.

You were absolutely right!. Thank you