Permalink adding a "-" to link

I’ve created a page with the year, example: x.com/2016 but the permalink will only save as x.com/2016-2. I don’t recall creating this page in the past. There’s nothing in my trash to empty. I’m at a loss. It wouldn’t be a big deal but I’ve already got 2500 postcards with /2016 and can’t change it at this point. Any suggestions would be helpful. Thanks