Used Turbo for many years. Last year clicked "Last Year Of Business" for side business. It wasn't. Business information has not carried over. How do I get this back?

If you indicated that last year was your "Last Year Of Business", then you business information is not going to carry-forward, because the assumption is that the business is now closed. 

If you restarted the business, then you'll have to re-enter the information manually.