My camera can not start after I upgraded it

My camera can not start after I upgraded it

I have upgraded my NX300 to firmware 1.45 by using Samsung i-launcher but then, I have been faced many problems especially lens (18-55cm III OIS) could not work properly. I fixed the lens error but I could not fix the autofocus by pushing trigger button. Some buttons on the body begun to work wrongly etc. I tried other firmwares to solve out the problems but I could not be successful.