1) Log off Ancestry from FTMM2 and quit FTMM2.
2) Log off of your Ancestry account from the site.
3) Clear the cache of the browser you use to access the Ancestry site. Quit browser and restart it.
4) Fire up browser and log on on to your Ancestry.com account
5) Fire up FTMM2 and log on to your Ancestry.com account.
If this doesn't clear up the issue, follow the same sequence, this time clearing the browser cookies as well as the cache.
If that doesn't work, call support and ask for a Mac genius, good luck with that ;).