Sale of section 179 property in 2nd year and listing on form 4797

So I sold a piece of equipment the year after I took the section 179 deduction. I entered the information in TT. When looking at form 4797, it put the sale price of the piece of equipment as a gain on sell of asset. It place that number as an amount I owe taxes on. The confussion some in on form 4797 where it filled out part IV and also list an amount on line 35. I would not think I would report the amount of the sale as gain and the amount on line 35 also as a gain to be taxed (of which TT did not put the amount on line 35 anywhere on another form). Why would it list any number in part IV, when it already said I have a gain in part III of the form?