I have pain in my knee while practising yoga. Can you suggest a solution?

Please double up your mat while practicing yoga. You can even place your mat over a carpet for more support.  Also, please expose the knee to sunlight every day for 60-90 minutes. Additionally, you can do alternate hot and cold fomentation around the painful part. Simply dip a cotton cloth and hot water and place them around the knee for 2-3 minutes. Then dip a cloth in cold water and wrap it around the knee for 2-3 minutes. Continue this process for about 10-15 minutes. Finally, leave a cold wet pack on for another 5-10 minutes. You can do this entire process 2-3 times a day for faster relief. During your yoga practice, please take frequent breaks to give your knees rest. Over time, your body will develop the strength and flexibility to practice with ease.