Hey @xxnq3i55_-76, welcome to the Spotify Community!
First, keep in mind that the Spotify app is only available on Samsung Smart TVs produced since 2015. If the model of your device is 2015 or newer, you should be able to use Spotify without a problem.
If that's the case, make sure your Smart TV has the latest software update installed. Also, we'd like you to reinstall the Spotify app one more time > Restart your smart TV and your internet connection > Try one more time.
You can find more info about how the service works on your Smart TV along with some troubleshooting steps here.
If you receive any errors, send us a screenshot.
Keep us posted.
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