@b00msie thanks will give it a go. First time it happened to me I lost about 5 hours can't imagine what you felt after loosing 50, sorry to hear about that.

Not looking good for this issue but 112 hours into Assassin's Creed Valhalla and the game no longer saves. Have on two occasions played 3 hours further into the game saved to two different save locations. The save has registered 115 hours played. So quit back to main menu then back to desktop and turned the xbox series x off. Next day switched on xbox loaded game progress had gone back to 112 hours played, armour upgrades I did in previous 3 hours disappeared, areas on the map that I had cleared of wealth / mysteries have come back quests completed returned too. Is there going to be a fix for this or is my game ruined? Grateful for some help!