Finding fossils in as good condition as old as Ardi is extremely rare.
Even Ardi is missing a knee joint—an element which would irrefutably determine her phylogenic place.
The following phylogenic tree is based on a 2019 study on hominin phylogeny at Cambridge University.
Notice how Ar. ramidus has its own branch.
Note: I am not sure why the spacing is all weird... Everything is in the right place horizontally but vertically stretched at the bottom!