Hello,
Sorry to be so late for the answer.
Subhajit was right : the new disk came from another MSA with the same (default) vdisk name. We pulled out the 2 new disk and the faulty vdisk with the same name dissappeared automaticly. I putted some new disk with no configuration on it and i could declere them as spare.
some everything is OK now.
Great thank's Subhajit !
Gérard