AMT Depr After 5/6/97 must be entered, I entered regular depreciation but it wants this also? Home Office

So I'm working on home office depreciation recapture.....which unfortunately I never took but it's not a huge amount.

 

It's somewhere around 1600 or so and just sold my home. 

 

So I entered it under the sale of a home depreciation after 1997 etc

 

However when I went to do the turbo tax analysis at the end, it now says AMT depreciation must be entered? 

 

The form asks for depreciation then AMT depreciation....I don't remember ever doing anything with AMT depreciation?

 

So confused.  Thanks!