You are using Windows operating system but unable to perform telnet.
You gets an error ‘telnet is not recognized as an internal or external command, operable program or batch file’ when you use a command prompt and try to telnet.
By default, Windows operating system does not have telnet client installed. Therefore, you will need to enable it manually.
You may install it by following the steps below:
Step 1: Click on the Start button.
Step 2: Type and select Control Panel.
Step 3: Select Turn Windows features on or off.
Step 4: Select the Telnet Client option.
Step 5: Click OK.
Step 6: Restart the computer
Please try performing the telnet via command prompt after you have enabled this respective service and you will receive a valid result.