Page Numbers Gone!

I'm working on a score in Musescore v1.3. After exporting, I noticed that there were no page numbers on any of the pages. I had changed some margins a little bit and put the paper size on Letter before this happened. I couldn't find anything regarding this problem online. I'm wondering if someone else has run into this and knows how to fix it. Any help is much appreciated!!

- Edit: So after messing with it a bit, it seems like it's just changing the paper size to Letter that gets rid of the page numbers. Anyone know why this is or how to fix it? Thanks in advance!