Problem with OLED Display Voltages (String Command) using transmitter and Receiver

[mubashirazmat]

@PaulRB

void loop()
{
  char buff[6];
  battery();
  dtostrf(Voltage, 5, 2, buff)
  Serial.print ("$ABC, ");
  Serial.print(buff);
  Serial.println("V,\n"); 
}

Thank you, its working; the voltags shows on my OLED but I m facing one problem ... I am not updated with my battery voltages everytime i need to shutdown an arduino and then power it again to show the voltages ...

Is there any way ?