Samsung 48'' TV Working but faulty. (Horn's Mill SG13)

This TV works but 4 pale dots have appeared on the screen, see photos. It started with one but they've gradually increased in number. Think it's on its way out, but offering it in case anyone wanted to try a repair or use it as a stopgap. It will connect to BBC iplayer, 4, Prime and Netflix but not ITVX or Channel 5.