diff --git a/extras/AT Command Manuals/SIM7000 Series AT Command Manual V1.03.pdf b/extras/AT Command Manuals/SIM7000 Series AT Command Manual V1.03.pdf
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index 8ab0e78..0000000
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diff --git a/extras/AT Command Manuals/SIM7000 Series_AT Command Manual_V1.04.pdf b/extras/AT Command Manuals/SIM7000 Series_AT Command Manual_V1.04.pdf
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index 0000000..a55e94b
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diff --git a/extras/AT Command Manuals/SIM7000 Series_TCPIP_Application Note_V1.01.pdf b/extras/AT Command Manuals/SIM7000 Series_TCPIP_Application Note_V1.01.pdf
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diff --git a/extras/AT Command Manuals/SIM800 Series_NTP_Application Note_V1.02.pdf b/extras/AT Command Manuals/SIM800 Series_NTP_Application Note_V1.02.pdf
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diff --git a/src/TinyGsmClientSIM800.h b/src/TinyGsmClientSIM800.h
index 283a4e5..02a53b6 100644
--- a/src/TinyGsmClientSIM800.h
+++ b/src/TinyGsmClientSIM800.h
@@ -704,78 +704,65 @@ TINY_GSM_MODEM_WAIT_FOR_NETWORK()
     waitResponse();
     return true;
   }
-  
+
   /*
    * NTP server functions
    */
-  boolean isValidNumber(String str)
-{
-   boolean isNum = false;
-   if(!(str.charAt(0) == '+' || str.charAt(0) == '-' || isDigit(str.charAt(0)))) return false;
+  boolean isValidNumber(String str) {
+    boolean isNum = false;
+    if(!(str.charAt(0) == '+' || str.charAt(0) == '-' || isDigit(str.charAt(0)))) return false;
 
-   for(byte i=1;i < str.length(); i++)
-   {
-       if(!(isDigit(str.charAt(i)) || str.charAt(i) == '.')) return false;
-   }
-   return true;
-}
-
-String ShowNTPError(byte error)
-{
-  switch (error)
-  {
-    case 1:
-      return "Network time synchronization is successful";
-    case 61:
-      return "Network error";
-    case 62:
-      return "DNS resolution error";
-    case 63:
-      return "Connection error";
-    case 64:
-      return "Service response error";
-    case 65:
-      return "Service response timeout";
-    default:
-      return "Unknown error: " + String(error);
-  }
-}
-  
-byte NTPServerSync(String server = "pool.ntp.org", byte TimeZone = 3)
-{
-  //Serial.println("Sync time with NTP server.");
-  sendAT(GF("+CNTPCID=1"));
-  if (waitResponse(10000L) != 1) 
-  {
-      //Serial.println("AT command \"AT+CNTPCID=1\" executing fault.");
-      return -1; 
+    for(byte i=1;i < str.length(); i++) {
+      if(!(isDigit(str.charAt(i)) || str.charAt(i) == '.')) return false;
+    }
+    return true;
   }
 
-  String CNTP = "+CNTP=" + server + "," + String(TimeZone);   
-  sendAT(GF(CNTP));
-  if (waitResponse(10000L) != 1) 
-  {
-      //Serial.println("AT command \"" + CNTP + "\" executing fault.");
-      return -1;
-  }
+  String ShowNTPError(byte error) {
+    switch (error) {
+      case 1:
+        return "Network time synchronization is successful";
+      case 61:
+        return "Network error";
+      case 62:
+        return "DNS resolution error";
+      case 63:
+        return "Connection error";
+      case 64:
+        return "Service response error";
+      case 65:
+        return "Service response timeout";
+      default:
+        return "Unknown error: " + String(error);
+    }
+  }
+
+  byte NTPServerSync(String server = "pool.ntp.org", byte TimeZone = 3) {
+    //Serial.println("Sync time with NTP server.");
+    sendAT(GF("+CNTPCID=1"));
+    if (waitResponse(10000L) != 1) {
+        return -1;
+    }
 
-  sendAT(GF("+CNTP"));
-  if (waitResponse(10000L, GF(GSM_NL "+CNTP:")))
-  {
-      String result = stream.readStringUntil('\n');
-      result.trim();
-      if (isValidNumber(result))
-      {
-        return result.toInt();
-      }
-  }
-  else
-  {
-    //Serial.println("AT command \"+CNTP\" executing fault.");
+    sendAT(GF("+CNTP="), server, ',', String(TimeZone));
+    if (waitResponse(10000L) != 1) {
+        return -1;
+    }
+
+    sendAT(GF("+CNTP"));
+    if (waitResponse(10000L, GF(GSM_NL "+CNTP:"))) {
+        String result = stream.readStringUntil('\n');
+        result.trim();
+        if (isValidNumber(result))
+        {
+          return result.toInt();
+        }
+    }
+    else {
+      return -1;
+    }
     return -1;
-  }  
-  return -1;
-}
+  }
 
   float getTemperature() TINY_GSM_ATTR_NOT_AVAILABLE;