@pelquilmes: Are you using Smart View on your S10+ to mirror to your TV? If not, swipe from the top of the screen to the bottom, select Smart View from the Quick Settings panel, select your TV from the list of available devices and you should be good to go. Depending on your TV model, you may need to enable Screen Mirroring manually via the Source menu. If you have an external drive connected to the S10+, try moving one of the video files to your internal storage to see if you're able to mirror it in this fashion via the My Videos option. For further screen mirroring options, please check the link below.