Neponyatki with the save:( (Days Gone)

Good evening. Bought in playstore the game began to pass. Walked a couple of episodes,but in the middle of the third had to leave, saved. When I went back to my save,the episode started again from the beginning,and so every save(( Tell me pliz,this is as it should be that we should go an episode without leaving the game or is it a bug? If it should,then why manual saving.