It’s been total silence between cancer-stricken King Charles III and his son Prince Harry. Despite Charles’ ongoing health battle, the British king has stopped answering the royal renegade’s phone calls, RadarOnline.com can reveal. Harry, 39, made a quick trip across the pond in February after learning about his father’s cancer diagnosis. The visit was short-lived, though, with the Duke of Sussex only briefly meeting with Charles, 75, before he traveled back home to wife Meghan Markle and their two children – Archie, 4, and Lilibet, 2 – in California. Since then, communication between Charles …