with "turn wifi off" do you mean
WiFi.disconnect()
?
or do you mean
void setModemSleep() {
WiFi.setSleep(true);
if` `(!setCpuFrequencyMhz(40)){
Serial2.println("Not valid frequency!");
}
// Use this if 40Mhz is not supported
// setCpuFrequencyMhz(80);
}
void wakeModemSleep() {
setCpuFrequencyMhz(240);
}
or
void disableWiFi(){
adc_power_off();
WiFi.disconnect(true); // Disconnect from the network
WiFi.mode(WIFI_OFF); // Switch WiFi off
}