@wachfiha: Please try heading to Settings > Battery and device care > Optimise now, followed by Memory > Clean now. Also, head to Settings > Apps > Camera > Force stop > Storage > Clear cache, then restart your Galaxy S21 FE.
If you continue to see the 'Camera Failed' message when you launch the Camera app, then please head to the Samsung Members app > Press and hold on the app icon > Diagnostics > Camera, and follow the on screen instructions. If this test flags any issues, or says 'Action required', then please head to samsung.com > Scroll down to the bottom of the page > Contact us, and get in touch via your preferred channel, and an advisor will be on hand to assist you further and arrange for the phone to be inspected under warranty.
