[Share]-Share tab isn't working in XD.

I have been working in and out of a prototype for some time with no issue when it comes to sharing with my team of developers. However, now, literally in just this one document, I can no longer share my work. When I click "Share," nothing happens. It stays on the previous tab, albeit with the options grayed out.

I have made no changes aside from building a new artboard with zero components within it.  

Help!

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