How do I fix issues im having with WhatsApp camera, video calling and now the camera in general?

My Son has a Samsung A04 and has recently out the blue getting a **whatsapp error that states: Whatsapp was unable to start the camera. if you continue to experience issues with the camera, please restart your device.** Cool so i did just that.. Restart.. try video call again, same issue. Next uninstall Whatsapp, restart phone, reinstall whatsapp, do the setup again, try to video call, and it worked. directly after the test video call he tries to video call his mom and same error came up again. now after trying to search for a fix another system error came up the reads: **com.sec.Android.app.camerasaver keeps stopping.** I have cleared the cache of both camera and whatsapp apps, and whatsapp has all the permissions it possibly can get. But now when im trying to open the camera app that comes with the phone it also says: **couldnt open camera, Try Again** **Please Help!!!!**