Best thing to do would be to turn off the camera and replace the batteries while also extracting the memory card, once memory card is in place and batteries are in wait 1-2 minutes and close battery cover. restart the camera
if that doesnt work try gently twisting the lens as you turn it on until you hear a click, sometimes this doesnt always work.
another method is to put the camera face down and have the lens pointed towards the ceiling, while turning opn the camera hold the shutter button, this should be putting th ecamera into auto focus causing it to switch gears which should lock the lens back in place and have it working properly.
if still doesnt work call the manufacturer or a repair shop. try amazon also some cameras are sold for less than the cost of repair meaning repair could be up to 200 dollars while a replacement camera can be $81.45 on amazon. hope i helped!
Stephanie Flores, October 2008