My a730 camera is displaying a lens error message,

How long have you owned the camera? Is the lens stuck in the outward or inward position and does it move in and/or out at all when trying to turn it on/off. There are methods to try to fix it yourself. Like looking straight onto the lens and looking that is aligned the same all the way around. and if its not pushing it back into alignment. If the camera is under a year old I would have it serviced under warranty. Once I have more information I can assist you further.
Thanks,
Lee