Educon Template / Everything disappears after inserting a photo/ bug issue.

I was working with the quickstart version of the educon template with SP Page Builder. I inserted a block that had a photo in it. When I tried to replace the photo, everything on the page disappered including the block I was working on. I tried using a different photo and the same thing happeed. I tried a different block and the same thing happend. I tried just inserting a photo and the same thing happened. It did not happen when I first started working on the page and put a hero block in. I was able to change that picture. Can you please help fix this bug?