Here are the steps you can take if your Smart TV is not recognizing your external hard drive:

1. Check if the hard drive is properly connected to the TV.
2. If so, check your TV has the latest available software updates.
3. Boot the external hard drive on a different device, such as a computer, to determine if it is working properly.
4. Check that your TVs compatibility requirements are fulfilled, such as power, connection type, and so on.
5. If all of the above is true and it won’t still recognize your hard drive, try performing a power cycle of the hard drive itself.