Smat Thing App via iOS phone unable to connect to TV to upload pictures

When I first bought the TV, Geek Squad set up Smart Things so that I could download pictures to the TV for the screen display. After about a year, it no longer works. The Geek Squad came back and could not fix it. The iPhone and the Samsung TV are connected to the same network. But he message on the Smart Things App is “not connected”. They cold booted the TV. It still won’t connect. Says it is offline. The only thing they didn’t try is to delete the app and reinstall install it because they did not want to delete the pictures I already had on there. Please let me know what I can do to make Smart Things App work. Thank you:)