I got my camera (a D3500) about a year and a half ago. It has worked fine up until this point but it has suddenly started taking completely black pictures, even though I can still see perfectly through the viewfinder. The first photo attached is what all photos I try to take look like. The second photo is what the screen looks like when I switch to live view. I was just wondering if you would have any idea what is wrong with it and how it could be fixed, if possible because I have no idea. Thank you!