The delay function not working for atmega4809 with updi serial

void setup()
{
pinMode(8,OUTPUT);
}
void loop()
{
digitalWrite(8,HIGH);
delay(1000);
digitalWrite(8,LOW);
delay(2000)

}

It won't compile, is that what you mean?

Please provide details of your setup

Which Arduino ?
What is it connected to ?
How is it connected ?

UKHeliBob:
Please provide details of your setup

Which Arduino ?
What is it connected to ?
How is it connected ?

A meaningful question would be useful too.