RF24 Only Works Once

That's a good ideal. I've put a 200ms delay but it is still the same.

Serial.println("About to transmit");
  // Did we manage to SUCCESSFULLY transmit that (by getting an acknowledgement back from the other Arduino)?
  // Even we didn't we'll continue with the sketch, you never know, the radio fairies may help us
  delay(200);
  if (!radio.write( &data, sizeof(unsigned char) )) {
    Serial.println("No acknowledgement of transmission - receiving radio device connected?");
    digitalWrite(redLed, HIGH);
    delay(1000);
    digitalWrite(redLed, LOW);
  } else {

Have increased that to 1000 but still the same.