Can't solve this Pb in Library Folder : kind of Dual view

I don't know how this happens :  All pictures are on my 😧 Hard Drive But Lightroom shows me 2 folder D drives (one is named "d:\" (lowcase) and the other  "D:\" (Upcase)

And the picture either in d:\ or in D:\ are in the same directory on the D drive : D:\my picture\2018-mm-dd but I can't see them all in the same "view" in Library Folder in Lightroom.

If I try to "move" them from a view to the other : LIGHTROOM says : "NOPE, Folder 2018-mm-dd already exist in 2018-mm"

That makes me angry ! any idea how to solve that ?

see above : the D drive appears 2 times and none is good !