As a quick and simple search on these forums will show; Samsung did something around the beginning of November 2019 to F up the screens and or the USB connection in the phones of A70 users. Can Samsung administrators please go find a tech and get them on this issue. It is not our phones or some app we have installed. It was a buggy update from Samsung. My phone has a near continous notification that the USB port is being connected and disconnected. This seems to cause the screen to not go to sleep. When the phone is plugged in, it works normally and goes to sleep.
Please go find someone capable of solving this.