Donut Chart Won't Group

[dss0025s]

Hello,

When I group together these two segments, they still are divided at a line and not unfied into one group. Is there any possible way to group them and then see them as combined?

[Padycosmos]

The technique I used might sound weird.  Immediately after grouping,, I clicked on the 'Undo' button and the result was this visual