What's the matter that the camera can't be turned on when Samsung mobile phone videos?

You can try to enter camera-photography mode-settings-reset-reset camera settings, enter mobile phone settings-application manager-all-click camera/WeChat/-to clear data, try to log in to WeChat to reconnect different contacts, uninstall micro /QQ messages and reinstall, try to update the next system version, and back up mobile phone data to restore mobile phone factory settings.

Generally, such problems are caused by the authorization of third-party applications. You should add WeChat software as a trusted application, find the option to allow access to the camera in the Settings-Applications-Security Center, check it, and then try to open the WeChat video call, which should solve the problem.