About to finish my return and my 1099 income has just been got counted twice; need to somehow erase one of those payments, so i go on and finish and pay my taxes. Help

Check your income on the form 1040.  Open one of the 1099s that were counted twice, then delete the form.  TT should recompute your amounts so that you can see that deleting the form actually worked.  
Then check your income again on the 1040.