The milis collide if the values are the same

Yes, I'll give it a try and find out why it can't create mailing lists at the same time, only with different variables. For example, you like the code below. So the led light will still be in the low position without blinking at all

unsigned long previousMillis1 = 0;
const long interval1 = 1000;
unsigned long previousMillis2 = 0;
const long interval2 = 1000;

void loop() {
   if(millis() - previousMillis1 >= interval1) {
      previousMillis1 = millis();
         lcd.clear();
         lcd.setCursor(0,0);
         lcd.print("test");
   }

  if (milis() - previousMillis2 >= interval2) {
    previousMillis2 = milis();
    if (ledState == LOW) {
      ledState = HIGH;
    } else {
      ledState = LOW;
    }
    digitalWrite(ledPin, ledState);
  }
}