Issue on php mysql toggle swtich change - php

Question

I am newbie to php and mysql. Using Cordova plugin for visual studio 2015 i have created a simple mobile application in which a user selects a serial number and on selecting it data is showed on the chart. Also there is a toggle switch button through which i can change the state of the switch from on-off or off-on. While changing the state the data is inserted into DB.
Now, i want is to do is that whenever i select a serial number the last state of the toggle should be shown on the switch. Means if the user has previously change the state from on to off for a particular serial number than this change should be shown if the same serial number is selected again.
For this i have done the following
My PHP CODE
require_once('config.php');
$dsn = $_REQUEST['Device_Serial_Number'];
$cmd_Name = isset($_REQUEST['Command_Name'])?$_REQUEST['Command_Name']:"";
$sqlFet = "select ADC.Server_Device_Command_ID , ADC.Device_ID ,
ADC.Server_Command_ID as Server_Command_ID, ASD.Command_Name
from ADS_Server_Device_Command ADC
inner join ADS_Server_Command ASD on adc.Server_Command_ID = asd.Server_Command_ID
inner join ADS_Device dsn on adc.Device_ID = dsn.Device_ID
where dsn.Device_Serial_Number = '$dsn'
order by adc.Server_Device_Command_ID desc LIMIT 1";
$result = mysqli_query($con,$sqlFet);
//print_r($result);
echo json_encode( (array) $result->fetch_object());
mysqli_close($con);
echo $cmd_Name;
My html(ajax) code
$.ajax({
method: "GET",
url: "http://localhost:Port/server/toggleFetch.php",
data: { Command_Name: tData , Device_Serial_Number: selectedVal },
success: function (data) {
var dt = $.parseJSON(JSON.stringify(data));
console.log(dt);
if (dt.Command_Name == "On") {
$("#cmn-toggle-7").prop('checked', true);
} else if (dt.Command_Name == "Off") {
console.log('else');
$("#cmn-toggle-7").prop('checked', false);
}
},
error: function () {
toastr.success('Data not fetched', '', { timeOut: 2000 })
}
});
Now whenever i run the app this part of code executes and it always goes to the else part. i.e if my serial number's last state is On it shows me off as shown in the below image
In above image you can clearly see that the command_Name = on but still it goes to else part.
I must be doing something wrong, and that i don't know.
Any help would be highly appreciated.