the preview turned into white and black line

I'm working on this design and suddenly got a pop-up box. I didn't get a good look at the message and after I hit "continue", because that was the only option available, my artboard turned like the image below. I tried to close it and open it again, it still the same I also try to relaunch my AI, but still the same. I even try to open it on another device, the file is still the same. Can some help me fix it, please...

I still have a lot of editing to do, and the due date is almost near.