Hello @MamtaR ,
that is really odd, but don't worry we are here to help! Have you checked if there are any updates for the Camera app and whether the lens is presenting any dust or damage?
You can check if there are any updates from the Samsung Galaxy Store app> Menu> My apps> Update all.
Do the same thing happens if you use the same Camera through a third party app (for example WhatsApp, Instagram, or any third party app that you use)?