Ghosts of War (2020) on Netflix

Plot summary

During the Allied advance through France in 1944, five paratroopers of the 82nd Airborne Division are posted to a chateau. On the way they ambush German troops driving a captured American jeep, leaving no survivors, and they meet a group of Jewish refugees. At the chateau they relieve the American guards, who leave in a hurry. Chris, who commands the detail, works out that a repetitive banging in the fireplace is Morse code, and Eugene translates the message: "I have no legs." Eugene then comes across a journal that a German soldier kept. It tells what became of the chateau's owners, the Helwig family, killed for sheltering Jews. When Eugene writes down a further message, his hand moves on its own to spell out that leaving means dying.