Thanks for trying to help that person--but I'm having a similar problem and changing the SSN does not help.

I submitted an amended return and it was rejected because of a minor issue. I fixed that and submitted again. Now it's rejected because it's a duplicate.  

The error message says "This submission is a duplicate of one that was previously received. Please contact customer support."

I've been searching for a week now and cannot find any way to contact something called "customer support."  Is there a phone #?

Or does anyone know a workaround for this?

Thank you!