Hi, I am himadri.I want to solve your problem.
Look carefully between the lens and the camera body for any sand, dirt or any damage etc. Try turning the camera with the lens facing down and shake to dislodge anything stuck and try removing batteries and memory card, wait 5minutes and refit the battery and let me know the result.
If you think you are not satisfied with my answer, then feel free to ask me further . And if your problem is solved then give me positive rating.