Go to your phone’s display settings menu and turn off Smart Stay to fix the issue temporarily.
Some users have reported that there seems to be a software error when the rear camera starts up, but only when this function is on, likely because Smart Stay is already using the front camera to detect when you’re looking at the screen so it stays on. If all of that doesn’t work, the problem likely has to do with Smart Stay.Use the Volume down button to scroll to Wipe Cache Partition and then press the Power button to begin. Turn the phone off, press the Power, Home, and Volume Up buttons together and hold until you see the Samsung logo pop up on the screen and the phone goes to its recovery mode. If clearing your camera app data and cache didn’t work, the wipe your cache partition.Then tap Force Stop, and go to the Storage menu, where you select Clear Data and Clear Cache. If restarting doesn’t work, clear the cache and data of the camera app by Settings > Applications > Application manager > Camera app.Have you ever met the issue ‘Camera Failed’ on your Samsung Galaxy S7 / S7 Edge, if you are look for a solution of this problem, try all of these steps in order, until one of them fixes your phone’s camera issue.
