title: SIM 7600CE not able to make a phone call nor able to send sms
body: <p>When I call the number inserted on the module it comes not reachable</p>
  <p>When I try to make a call the command returns ok but the call is not connected</p>
  <p>If I send an SMS to the inserted number am able to receive it and read it as well but can't send SMS its shows CMS ERROR: 500.</p>
  <p>This is the program to make a call</p>
  <pre><code>#!/usr/bin/python
  
  import RPi.GPIO as GPIO
  import serial
  import time
  
  ser = serial.Serial('/dev/ttyUSB2',115200)
  ser.flushInput()
  
  phone_number = '*********'
  power_key = 6
  rec_buff = ''
  
  def send_at(command,back,timeout):
      print (command)
      print (back)
      print (timeout)
      rec_buff = ''
      ser.write((command+'\r\n').encode())
      time.sleep(timeout)
      if ser.inWaiting():
          time.sleep(0.01 )
          rec_buff = ser.read(ser.inWaiting())
          print (rec_buff,)
      if back not in rec_buff.decode():
          print (command + ' ERROR')
          print (command + ' back:\t' + rec_buff.decode())
          return 0
      else:
          print (rec_buff.decode())
          return 1
  
  
  
  try:
      send_at('ATD'+phone_number+';','OK',1)
      time.sleep(20)
      ser.write('AT+CHUP\r\n'.encode())
      print ('Call disconnected')
  except :
      if ser != None:
          ser.close()
          GPIO.cleanup()
  
  #if ser != None:
  #   ser.close()
  #   GPIO.cleanup()
  
  
  
  </code></pre>
  <p>I get OK as output and the call disconnected message</p>
  <p>Connections: Have connected micro USB of the sim7600ce module to the USB port of the raspberry pi</p>
  <p><a href="https://i.stack.imgur.com/1XDH6.jpg" rel="nofollow noreferrer">SIM7600CE</a></p>
  <p>Am very new to this, please help me out</p>