Hello my name is***** do not rate until we are finished. I look forward to assisting and am very sorry to hear that you are having this problem. How are you holding it? For example have you tried putting it on a tripod or just down on something in general to see if the same thing happens?
That sounds like a possible lens issue, let me know what happens when you can.
Unfortunately as I mentioned that sounds like a lens issue. How old is it? Did you get an extended warranty?
Unfortunately no you would need a Sony technician to do it. You can not do it yourself. he lens has a part called a zoom unit that can cause this. It is normally part of the lens itself. You can still use the camera but will not be able to use the zoom until that is replaced. The price can vary and it is hard to find. You would need to call local shops for a price unfortunately. A lot of the time you have to get it from another camera with a different problem.