Screen has negitive picture and lines

Start the camera, go to the menus and set everything to factory default or original. Some cameras have a reset all to default.

Check to see if it is now okay.
If it continues to have problems, then it either needs repair or sell it as a repair or fix-it on a site such as Ebay.

Always check newer digital cameras for warranty coverage when the camera has problems which you cannot fix. Always worth the effort for a call to the manufacturer.