проблема с записью SD

У меня есть код Arduino для регистрации данных датчика, времени и даты. Затем я сохраняю все данные на SD-карте, а затем отправляю значение датчика на другой узел с помощью Lora. но я не могу записать данные на SD-карту. Пожалуйста, помогите мне решить эту проблему. Код также прилагается.

#include <RHReliableDatagram.h>
#include <RH_RF95.h>
#include "RTClib.h"
#include <SPI.h>
#include <SD.h>

RTC_DS1307 rtc;
File myFile;

#define node_address 12
uint8_t gateway_address = 11;
const int sensor_pin = A1;
float level;

/* Chip selection */
const int CS1 = 8;/*SD Card*/ 
const int CS2 = 10;/*LoRa*/ 

/* Configure LoRa driver */
RH_RF95 driver(10,2);
RHReliableDatagram manager(driver,node_address);

void setup () {
  pinMode(sensor_pin, INPUT);
  pinMode(CS1,OUTPUT);
  pinMode(CS2,OUTPUT);
// SPI.begin();`
  /*--------Serial port connection setup--------*/
  Serial.begin(9600);

  /*----------RTC Initialization----------*/
  Serial.println(F("Initializing RTC...!"));
  if (! rtc.begin()) {
    Serial.println(F("Couldn't find RTC"));
  }
  if (! rtc.isrunning()) {
    Serial.println(F("RTC is NOT running!"));
// rtc.adjust(DateTime(2019, 11, 12, 12, 32, 0)); // (Год, Месяц, Дата, Час, Мин, Сек)
  }

  /*----------SD CARD Initialization----------*/
  digitalWrite(CS2,HIGH);
  delay(500);
  digitalWrite(CS1,LOW);
  Serial.println(F("Initializing SD card..."));
  if (!SD.begin(CS1)) {
    Serial.println(F("initialization of SD Card is failed!"));
    return;
  }
  Serial.println(F("Initialization of SD Card is done."));
  /*----------LoRa Initialization----------*/
  digitalWrite(CS1,HIGH);
  delay(500);
  digitalWrite(CS2,LOW);
  if (manager.init())
  {
    Serial.println(F("LoRa Successfully Initialised "));
  } else {
    Serial.println(F("LoRa initialization failed"));
  }
  driver.setFrequency(433.0);
  driver.setTxPower(14,false);
  Serial.println();
}

void loop () {  
  DateTime now = rtc.now();
  /*----------Date----------*/
  Serial.print(now.year(), DEC);
  Serial.print('/');
  Serial.print(now.month(), DEC);
  Serial.print('/');
  Serial.print(now.day(), DEC);
  Serial.print(',');
  /*----------Time----------*/
  Serial.print(now.hour(), DEC);
  Serial.print(':');
  Serial.print(now.minute(), DEC);
  Serial.print(':');
  Serial.print(now.second(), DEC);
  Serial.println();

  /*----------SD card----------*/
  digitalWrite(CS2,HIGH);
  delay(500);
  digitalWrite(CS1,LOW);
  delay(100);
  myFile = SD.open("test.txt", FILE_WRITE); 
  if (myFile) {
    /*----------Saving Date----------*/
    myFile.print(now.year(), DEC);
    myFile.print('/');
    myFile.print(now.month(), DEC);
    myFile.print('/');
    myFile.print(now.day(), DEC);
    myFile.print(',');
    /*----------Saving Time----------*/
    myFile.print(now.hour(), DEC);
    myFile.print(':');
    myFile.print(now.minute(), DEC);
    myFile.print(':');
    myFile.print(now.second(), DEC);
    myFile.println(',');
    level = analogRead(sensor_pin);
    myFile.print(level);
    myFile.println();
    myFile.close();
  } else {
    Serial.println("Error opening test.txt");
  }
  delay(500);
  digitalWrite(CS1,HIGH);
  delay(500);
  digitalWrite(CS2,LOW);
  char data[RH_RF95_MAX_MESSAGE_LEN];
  sprintf(data,"$%d#%d",node_address,level);
  Serial.print("Level transferred is ");
  Serial.println(data);
  Serial.println(sizeof(data));
  if(!manager.sendtoWait((uint8_t*)data,sizeof(data),gateway_address))
  {
    Serial.println("Gateway offline");
  }
  delay(500);
}